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balances</title> <meta name="description" content="Search results for: covariate balances"> <meta name="keywords" content="covariate balances"> <meta name="viewport" content="width=device-width, initial-scale=1, minimum-scale=1, maximum-scale=1, user-scalable=no"> <meta charset="utf-8"> <link href="https://cdn.waset.org/favicon.ico" type="image/x-icon" rel="shortcut icon"> <link href="https://cdn.waset.org/static/plugins/bootstrap-4.2.1/css/bootstrap.min.css" rel="stylesheet"> <link href="https://cdn.waset.org/static/plugins/fontawesome/css/all.min.css" rel="stylesheet"> <link href="https://cdn.waset.org/static/css/site.css?v=150220211555" rel="stylesheet"> </head> <body> <header> <div class="container"> <nav class="navbar navbar-expand-lg navbar-light"> <a class="navbar-brand" href="https://waset.org"> <img src="https://cdn.waset.org/static/images/wasetc.png" alt="Open Science Research Excellence" title="Open Science Research Excellence" /> </a> <button class="d-block d-lg-none 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action="https://publications.waset.org/abstracts/search"> <div id="custom-search-input"> <div class="input-group"> <i class="fas fa-search"></i> <input type="text" class="search-query" name="q" placeholder="Author, Title, Abstract, Keywords" value="covariate balances"> <input type="submit" class="btn_search" value="Search"> </div> </div> </form> </div> </div> <div class="row mt-3"> <div class="col-sm-3"> <div class="card"> <div class="card-body"><strong>Commenced</strong> in January 2007</div> </div> </div> <div class="col-sm-3"> <div class="card"> <div class="card-body"><strong>Frequency:</strong> Monthly</div> </div> </div> <div class="col-sm-3"> <div class="card"> <div class="card-body"><strong>Edition:</strong> International</div> </div> </div> <div class="col-sm-3"> <div class="card"> <div class="card-body"><strong>Paper Count:</strong> 148</div> </div> </div> </div> <h1 class="mt-3 mb-3 text-center" style="font-size:1.6rem;">Search results for: covariate balances</h1> <div class="card paper-listing mb-3 mt-3"> <h5 class="card-header" style="font-size:.9rem"><span class="badge badge-info">148</span> Minimizing the Impact of Covariate Detection Limit in Logistic Regression</h5> <div class="card-body"> <p class="card-text"><strong>Authors:</strong> <a href="https://publications.waset.org/abstracts/search?q=Shahadut%20Hossain">Shahadut Hossain</a>, <a href="https://publications.waset.org/abstracts/search?q=Jacek%20Wesolowski"> Jacek Wesolowski</a>, <a href="https://publications.waset.org/abstracts/search?q=Zahirul%20Hoque"> Zahirul Hoque</a> </p> <p class="card-text"><strong>Abstract:</strong></p> In many epidemiological and environmental studies covariate measurements are subject to the detection limit. In most applications, covariate measurements are usually truncated from below which is known as left-truncation. Because the measuring device, which we use to measure the covariate, fails to detect values falling below the certain threshold. In regression analyses, it causes inflated bias and inaccurate mean squared error (MSE) to the estimators. This paper suggests a response-based regression calibration method to correct the deleterious impact introduced by the covariate detection limit in the estimators of the parameters of simple logistic regression model. Compared to the maximum likelihood method, the proposed method is computationally simpler, and hence easier to implement. It is robust to the violation of distributional assumption about the covariate of interest. In producing correct inference, the performance of the proposed method compared to the other competing methods has been investigated through extensive simulations. A real-life application of the method is also shown using data from a population-based case-control study of non-Hodgkin lymphoma. <p class="card-text"><strong>Keywords:</strong> <a href="https://publications.waset.org/abstracts/search?q=environmental%20exposure" title="environmental exposure">environmental exposure</a>, <a href="https://publications.waset.org/abstracts/search?q=detection%20limit" title=" detection limit"> detection limit</a>, <a href="https://publications.waset.org/abstracts/search?q=left%20truncation" title=" left truncation"> left truncation</a>, <a href="https://publications.waset.org/abstracts/search?q=bias" title=" bias"> bias</a>, <a href="https://publications.waset.org/abstracts/search?q=ad-hoc%20substitution" title=" ad-hoc substitution"> ad-hoc substitution</a> </p> <a href="https://publications.waset.org/abstracts/55567/minimizing-the-impact-of-covariate-detection-limit-in-logistic-regression" class="btn btn-primary btn-sm">Procedia</a> <a href="https://publications.waset.org/abstracts/55567.pdf" target="_blank" class="btn btn-primary btn-sm">PDF</a> <span class="bg-info text-light px-1 py-1 float-right rounded"> Downloads <span class="badge badge-light">236</span> </span> </div> </div> <div class="card paper-listing mb-3 mt-3"> <h5 class="card-header" style="font-size:.9rem"><span class="badge badge-info">147</span> Generalized Additive Model for Estimating Propensity Score</h5> <div class="card-body"> <p class="card-text"><strong>Authors:</strong> <a href="https://publications.waset.org/abstracts/search?q=Tahmidul%20Islam">Tahmidul Islam</a> </p> <p class="card-text"><strong>Abstract:</strong></p> Propensity Score Matching (PSM) technique has been widely used for estimating causal effect of treatment in observational studies. One major step of implementing PSM is estimating the propensity score (PS). Logistic regression model with additive linear terms of covariates is most used technique in many studies. Logistics regression model is also used with cubic splines for retaining flexibility in the model. However, choosing the functional form of the logistic regression model has been a question since the effectiveness of PSM depends on how accurately the PS been estimated. In many situations, the linearity assumption of linear logistic regression may not hold and non-linear relation between the logit and the covariates may be appropriate. One can estimate PS using machine learning techniques such as random forest, neural network etc for more accuracy in non-linear situation. In this study, an attempt has been made to compare the efficacy of Generalized Additive Model (GAM) in various linear and non-linear settings and compare its performance with usual logistic regression. GAM is a non-parametric technique where functional form of the covariates can be unspecified and a flexible regression model can be fitted. In this study various simple and complex models have been considered for treatment under several situations (small/large sample, low/high number of treatment units) and examined which method leads to more covariate balance in the matched dataset. It is found that logistic regression model is impressively robust against inclusion quadratic and interaction terms and reduces mean difference in treatment and control set equally efficiently as GAM does. GAM provided no significantly better covariate balance than logistic regression in both simple and complex models. The analysis also suggests that larger proportion of controls than treatment units leads to better balance for both of the methods. <p class="card-text"><strong>Keywords:</strong> <a href="https://publications.waset.org/abstracts/search?q=accuracy" title="accuracy">accuracy</a>, <a href="https://publications.waset.org/abstracts/search?q=covariate%20balances" title=" covariate balances"> covariate balances</a>, <a href="https://publications.waset.org/abstracts/search?q=generalized%20additive%20model" title=" generalized additive model"> generalized additive model</a>, <a href="https://publications.waset.org/abstracts/search?q=logistic%20regression" title=" logistic regression"> logistic regression</a>, <a href="https://publications.waset.org/abstracts/search?q=non-linearity" title=" non-linearity"> non-linearity</a>, <a href="https://publications.waset.org/abstracts/search?q=propensity%20score%20matching" title=" propensity score matching"> propensity score matching</a> </p> <a href="https://publications.waset.org/abstracts/40433/generalized-additive-model-for-estimating-propensity-score" class="btn btn-primary btn-sm">Procedia</a> <a href="https://publications.waset.org/abstracts/40433.pdf" target="_blank" class="btn btn-primary btn-sm">PDF</a> <span class="bg-info text-light px-1 py-1 float-right rounded"> Downloads <span class="badge badge-light">367</span> </span> </div> </div> <div class="card paper-listing mb-3 mt-3"> <h5 class="card-header" style="font-size:.9rem"><span class="badge badge-info">146</span> Survival and Hazard Maximum Likelihood Estimator with Covariate Based on Right Censored Data of Weibull Distribution</h5> <div class="card-body"> <p class="card-text"><strong>Authors:</strong> <a href="https://publications.waset.org/abstracts/search?q=Al%20Omari%20Mohammed%20Ahmed">Al Omari Mohammed Ahmed</a> </p> <p class="card-text"><strong>Abstract:</strong></p> This paper focuses on Maximum Likelihood Estimator with Covariate. Covariates are incorporated into the Weibull model. Under this regression model with regards to maximum likelihood estimator, the parameters of the covariate, shape parameter, survival function and hazard rate of the Weibull regression distribution with right censored data are estimated. The mean square error (MSE) and absolute bias are used to compare the performance of Weibull regression distribution. For the simulation comparison, the study used various sample sizes and several specific values of the Weibull shape parameter. <p class="card-text"><strong>Keywords:</strong> <a href="https://publications.waset.org/abstracts/search?q=weibull%20regression%20distribution" title="weibull regression distribution">weibull regression distribution</a>, <a href="https://publications.waset.org/abstracts/search?q=maximum%20likelihood%20estimator" title=" maximum likelihood estimator"> maximum likelihood estimator</a>, <a href="https://publications.waset.org/abstracts/search?q=survival%20function" title=" survival function"> survival function</a>, <a href="https://publications.waset.org/abstracts/search?q=hazard%20rate" title=" hazard rate"> hazard rate</a>, <a href="https://publications.waset.org/abstracts/search?q=right%20censoring" title=" right censoring"> right censoring</a> </p> <a href="https://publications.waset.org/abstracts/40164/survival-and-hazard-maximum-likelihood-estimator-with-covariate-based-on-right-censored-data-of-weibull-distribution" class="btn btn-primary btn-sm">Procedia</a> <a href="https://publications.waset.org/abstracts/40164.pdf" target="_blank" class="btn btn-primary btn-sm">PDF</a> <span class="bg-info text-light px-1 py-1 float-right rounded"> Downloads <span class="badge badge-light">441</span> </span> </div> </div> <div class="card paper-listing mb-3 mt-3"> <h5 class="card-header" style="font-size:.9rem"><span class="badge badge-info">145</span> Spatial Point Process Analysis of Dengue Fever in Tainan, Taiwan</h5> <div class="card-body"> <p class="card-text"><strong>Authors:</strong> <a href="https://publications.waset.org/abstracts/search?q=Ya-Mei%20Chang">Ya-Mei Chang</a> </p> <p class="card-text"><strong>Abstract:</strong></p> This research is intended to apply spatio-temporal point process methods to the dengue fever data in Tainan. The spatio-temporal intensity function of the dataset is assumed to be separable. The kernel estimation is a widely used approach to estimate intensity functions. The intensity function is very helpful to study the relation of the spatio-temporal point process and some covariates. The covariate effects might be nonlinear. An nonparametric smoothing estimator is used to detect the nonlinearity of the covariate effects. A fitted parametric model could describe the influence of the covariates to the dengue fever. The correlation between the data points is detected by the K-function. The result of this research could provide useful information to help the government or the stakeholders making decisions. <p class="card-text"><strong>Keywords:</strong> <a href="https://publications.waset.org/abstracts/search?q=dengue%20fever" title="dengue fever">dengue fever</a>, <a href="https://publications.waset.org/abstracts/search?q=spatial%20point%20process" title=" spatial point process"> spatial point process</a>, <a href="https://publications.waset.org/abstracts/search?q=kernel%20estimation" title=" kernel estimation"> kernel estimation</a>, <a href="https://publications.waset.org/abstracts/search?q=covariate%20effect" title=" covariate effect"> covariate effect</a> </p> <a href="https://publications.waset.org/abstracts/66856/spatial-point-process-analysis-of-dengue-fever-in-tainan-taiwan" class="btn btn-primary btn-sm">Procedia</a> <a href="https://publications.waset.org/abstracts/66856.pdf" target="_blank" class="btn btn-primary btn-sm">PDF</a> <span class="bg-info text-light px-1 py-1 float-right rounded"> Downloads <span class="badge badge-light">351</span> </span> </div> </div> <div class="card paper-listing mb-3 mt-3"> <h5 class="card-header" style="font-size:.9rem"><span class="badge badge-info">144</span> Bayesian Reliability of Weibull Regression with Type-I Censored Data</h5> <div class="card-body"> <p class="card-text"><strong>Authors:</strong> <a href="https://publications.waset.org/abstracts/search?q=Al%20Omari%20Moahmmed%20Ahmed">Al Omari Moahmmed Ahmed </a> </p> <p class="card-text"><strong>Abstract:</strong></p> In the Bayesian, we developed an approach by using non-informative prior with covariate and obtained by using Gauss quadrature method to estimate the parameters of the covariate and reliability function of the Weibull regression distribution with Type-I censored data. The maximum likelihood seen that the estimators obtained are not available in closed forms, although they can be solved it by using Newton-Raphson methods. The comparison criteria are the MSE and the performance of these estimates are assessed using simulation considering various sample size, several specific values of shape parameter. The results show that Bayesian with non-informative prior is better than Maximum Likelihood Estimator. <p class="card-text"><strong>Keywords:</strong> <a href="https://publications.waset.org/abstracts/search?q=non-informative%20prior" title="non-informative prior">non-informative prior</a>, <a href="https://publications.waset.org/abstracts/search?q=Bayesian%20method" title=" Bayesian method"> Bayesian method</a>, <a href="https://publications.waset.org/abstracts/search?q=type-I%20censoring" title=" type-I censoring"> type-I censoring</a>, <a href="https://publications.waset.org/abstracts/search?q=Gauss%20quardature" title=" Gauss quardature"> Gauss quardature</a> </p> <a href="https://publications.waset.org/abstracts/18728/bayesian-reliability-of-weibull-regression-with-type-i-censored-data" class="btn btn-primary btn-sm">Procedia</a> <a href="https://publications.waset.org/abstracts/18728.pdf" target="_blank" class="btn btn-primary btn-sm">PDF</a> <span class="bg-info text-light px-1 py-1 float-right rounded"> Downloads <span class="badge badge-light">504</span> </span> </div> </div> <div class="card paper-listing mb-3 mt-3"> <h5 class="card-header" style="font-size:.9rem"><span class="badge badge-info">143</span> An Efficient Propensity Score Method for Causal Analysis With Application to Case-Control Study in Breast Cancer Research</h5> <div class="card-body"> <p class="card-text"><strong>Authors:</strong> <a href="https://publications.waset.org/abstracts/search?q=Ms%20Azam%20Najafkouchak">Ms Azam Najafkouchak</a>, <a href="https://publications.waset.org/abstracts/search?q=David%20Todem"> David Todem</a>, <a href="https://publications.waset.org/abstracts/search?q=Dorothy%20Pathak"> Dorothy Pathak</a>, <a href="https://publications.waset.org/abstracts/search?q=Pramod%20Pathak"> Pramod Pathak</a>, <a href="https://publications.waset.org/abstracts/search?q=Joseph%20Gardiner"> Joseph Gardiner</a> </p> <p class="card-text"><strong>Abstract:</strong></p> Propensity score (PS) methods have recently become the standard analysis as a tool for the causal inference in the observational studies where exposure is not randomly assigned, thus, confounding can impact the estimation of treatment effect on the outcome. For the binary outcome, the effect of treatment on the outcome can be estimated by odds ratios, relative risks, and risk differences. However, using the different PS methods may give you a different estimation of the treatment effect on the outcome. Several methods of PS analyses have been used mainly, include matching, inverse probability of weighting, stratification, and covariate adjusted on PS. Due to the dangers of discretizing continuous variables (exposure, covariates), the focus of this paper will be on how the variation in cut-points or boundaries will affect the average treatment effect (ATE) utilizing the stratification of PS method. Therefore, we are trying to avoid choosing arbitrary cut-points, instead, we continuously discretize the PS and accumulate information across all cut-points for inferences. We will use Monte Carlo simulation to evaluate ATE, focusing on two PS methods, stratification and covariate adjusted on PS. We will then show how this can be observed based on the analyses of the data from a case-control study of breast cancer, the Polish Women’s Health Study. <p class="card-text"><strong>Keywords:</strong> <a href="https://publications.waset.org/abstracts/search?q=average%20treatment%20effect" title="average treatment effect">average treatment effect</a>, <a href="https://publications.waset.org/abstracts/search?q=propensity%20score" title=" propensity score"> propensity score</a>, <a href="https://publications.waset.org/abstracts/search?q=stratification" title=" stratification"> stratification</a>, <a href="https://publications.waset.org/abstracts/search?q=covariate%20adjusted" title=" covariate adjusted"> covariate adjusted</a>, <a href="https://publications.waset.org/abstracts/search?q=monte%20Calro%20estimation" title=" monte Calro estimation"> monte Calro estimation</a>, <a href="https://publications.waset.org/abstracts/search?q=breast%20cancer" title=" breast cancer"> breast cancer</a>, <a href="https://publications.waset.org/abstracts/search?q=case_control%20study" title=" case_control study"> case_control study</a> </p> <a href="https://publications.waset.org/abstracts/152765/an-efficient-propensity-score-method-for-causal-analysis-with-application-to-case-control-study-in-breast-cancer-research" class="btn btn-primary btn-sm">Procedia</a> <a href="https://publications.waset.org/abstracts/152765.pdf" target="_blank" class="btn btn-primary btn-sm">PDF</a> <span class="bg-info text-light px-1 py-1 float-right rounded"> Downloads <span class="badge badge-light">105</span> </span> </div> </div> <div class="card paper-listing mb-3 mt-3"> <h5 class="card-header" style="font-size:.9rem"><span class="badge badge-info">142</span> The Effect of Political Characteristics on the Budget Balance of Local Governments: A Dynamic System Generalized Method of Moments Data Approach</h5> <div class="card-body"> <p class="card-text"><strong>Authors:</strong> <a href="https://publications.waset.org/abstracts/search?q=Stefanie%20M.%20Vanneste">Stefanie M. Vanneste</a>, <a href="https://publications.waset.org/abstracts/search?q=Stijn%20Goeminne"> Stijn Goeminne</a> </p> <p class="card-text"><strong>Abstract:</strong></p> This paper studies the effect of political characteristics of 308 Flemish municipalities on their budget balance in the period 1995-2011. All local governments experience the same economic and financial setting, however some governments have high budget balances, while others have low budget balances. The aim of this paper is to explain the differences in municipal budget balances by a number of economic, socio-demographic and political variables. The economic and socio-demographic variables will be used as control variables, while the focus of this paper will be on the political variables. We test four hypotheses resulting from the literature, namely (i) the partisan hypothesis tests if left wing governments have lower budget balances, (ii) the fragmentation hypothesis stating that more fragmented governments have lower budget balances, (iii) the hypothesis regarding the power of the government, higher powered governments would resolve in higher budget balances, and (iv) the opportunistic budget cycle to test whether politicians manipulate the economic situation before elections in order to maximize their reelection possibilities and therefore have lower budget balances before elections. The contributions of our paper to the existing literature are multiple. First, we use the whole array of political variables and not just a selection of them. Second, we are dealing with a homogeneous database with the same budget and election rules, making it easier to focus on the political factors without having to control for the impact of differences in the political systems. Third, our research extends the existing literature on Flemish municipalities as this is the first dynamic research on local budget balances. We use a dynamic panel data model. Because of the two lagged dependent variables as explanatory variables, we employ the system GMM (Generalized Method of Moments) estimator. This is the best possible estimator as we are dealing with political panel data that is rather persistent. Our empirical results show that the effect of the ideological position and the power of the coalition are of less importance to explain the budget balance. The political fragmentation of the government on the other hand has a negative and significant effect on the budget balance. The more parties in a coalition the worse the budget balance is ceteris paribus. Our results also provide evidence of an opportunistic budget cycle, the budget balances are lower in pre-election years relative to the other years to try and increase the incumbents reelection possibilities. An additional finding is that the incremental effect of the budget balance is very important and should not be ignored like is being done in a lot of empirical research. The coefficients of the lagged dependent variables are always positive and very significant. This proves that the budget balance is subject to incrementalism. It is not possible to change the entire policy from one year to another so the actions taken in recent past years still have an impact on the current budget balance. Only a relatively small amount of research concerning the budget balance takes this considerable incremental effect into account. Our findings survive several robustness checks. <p class="card-text"><strong>Keywords:</strong> <a href="https://publications.waset.org/abstracts/search?q=budget%20balance" title="budget balance">budget balance</a>, <a href="https://publications.waset.org/abstracts/search?q=fragmentation" title=" fragmentation"> fragmentation</a>, <a href="https://publications.waset.org/abstracts/search?q=ideology" title=" ideology"> ideology</a>, <a href="https://publications.waset.org/abstracts/search?q=incrementalism" title=" incrementalism"> incrementalism</a>, <a href="https://publications.waset.org/abstracts/search?q=municipalities" title=" municipalities"> municipalities</a>, <a href="https://publications.waset.org/abstracts/search?q=opportunistic%20budget%20cycle" title=" opportunistic budget cycle"> opportunistic budget cycle</a>, <a href="https://publications.waset.org/abstracts/search?q=panel%20data" title=" panel data"> panel data</a>, <a href="https://publications.waset.org/abstracts/search?q=political%20characteristics" title=" political characteristics"> political characteristics</a>, <a href="https://publications.waset.org/abstracts/search?q=power" title=" power"> power</a>, <a href="https://publications.waset.org/abstracts/search?q=system%20GMM" title=" system GMM"> system GMM</a> </p> <a href="https://publications.waset.org/abstracts/69181/the-effect-of-political-characteristics-on-the-budget-balance-of-local-governments-a-dynamic-system-generalized-method-of-moments-data-approach" class="btn btn-primary btn-sm">Procedia</a> <a href="https://publications.waset.org/abstracts/69181.pdf" target="_blank" class="btn btn-primary btn-sm">PDF</a> <span class="bg-info text-light px-1 py-1 float-right rounded"> Downloads <span class="badge badge-light">299</span> </span> </div> </div> <div class="card paper-listing mb-3 mt-3"> <h5 class="card-header" style="font-size:.9rem"><span class="badge badge-info">141</span> Covariate-Adjusted Response-Adaptive Designs for Semi-Parametric Survival Responses</h5> <div class="card-body"> <p class="card-text"><strong>Authors:</strong> <a href="https://publications.waset.org/abstracts/search?q=Ayon%20Mukherjee">Ayon Mukherjee</a> </p> <p class="card-text"><strong>Abstract:</strong></p> Covariate-adjusted response-adaptive (CARA) designs use the available responses to skew the treatment allocation in a clinical trial in towards treatment found at an interim stage to be best for a given patient's covariate profile. Extensive research has been done on various aspects of CARA designs with the patient responses assumed to follow a parametric model. However, ranges of application for such designs are limited in real-life clinical trials where the responses infrequently fit a certain parametric form. On the other hand, robust estimates for the covariate-adjusted treatment effects are obtained from the parametric assumption. To balance these two requirements, designs are developed which are free from distributional assumptions about the survival responses, relying only on the assumption of proportional hazards for the two treatment arms. The proposed designs are developed by deriving two types of optimum allocation designs, and also by using a distribution function to link the past allocation, covariate and response histories to the present allocation. The optimal designs are based on biased coin procedures, with a bias towards the better treatment arm. These are the doubly-adaptive biased coin design (DBCD) and the efficient randomized adaptive design (ERADE). The treatment allocation proportions for these designs converge to the expected target values, which are functions of the Cox regression coefficients that are estimated sequentially. These expected target values are derived based on constrained optimization problems and are updated as information accrues with sequential arrival of patients. The design based on the link function is derived using the distribution function of a probit model whose parameters are adjusted based on the covariate profile of the incoming patient. To apply such designs, the treatment allocation probabilities are sequentially modified based on the treatment allocation history, response history, previous patients’ covariates and also the covariates of the incoming patient. Given these information, an expression is obtained for the conditional probability of a patient allocation to a treatment arm. Based on simulation studies, it is found that the ERADE is preferable to the DBCD when the main aim is to minimize the variance of the observed allocation proportion and to maximize the power of the Wald test for a treatment difference. However, the former procedure being discrete tends to be slower in converging towards the expected target allocation proportion. The link function based design achieves the highest skewness of patient allocation to the best treatment arm and thus ethically is the best design. Other comparative merits of the proposed designs have been highlighted and their preferred areas of application are discussed. It is concluded that the proposed CARA designs can be considered as suitable alternatives to the traditional balanced randomization designs in survival trials in terms of the power of the Wald test, provided that response data are available during the recruitment phase of the trial to enable adaptations to the designs. Moreover, the proposed designs enable more patients to get treated with the better treatment during the trial thus making the designs more ethically attractive to the patients. An existing clinical trial has been redesigned using these methods. <p class="card-text"><strong>Keywords:</strong> <a href="https://publications.waset.org/abstracts/search?q=censored%20response" title="censored response">censored response</a>, <a href="https://publications.waset.org/abstracts/search?q=Cox%20regression" title=" Cox regression"> Cox regression</a>, <a href="https://publications.waset.org/abstracts/search?q=efficiency" title=" efficiency"> efficiency</a>, <a href="https://publications.waset.org/abstracts/search?q=ethics" title=" ethics"> ethics</a>, <a href="https://publications.waset.org/abstracts/search?q=optimal%20allocation" title=" optimal allocation"> optimal allocation</a>, <a href="https://publications.waset.org/abstracts/search?q=power" title=" power"> power</a>, <a href="https://publications.waset.org/abstracts/search?q=variability" title=" variability"> variability</a> </p> <a href="https://publications.waset.org/abstracts/91902/covariate-adjusted-response-adaptive-designs-for-semi-parametric-survival-responses" class="btn btn-primary btn-sm">Procedia</a> <a href="https://publications.waset.org/abstracts/91902.pdf" target="_blank" class="btn btn-primary btn-sm">PDF</a> <span class="bg-info text-light px-1 py-1 float-right rounded"> Downloads <span class="badge badge-light">165</span> </span> </div> </div> <div class="card paper-listing mb-3 mt-3"> <h5 class="card-header" style="font-size:.9rem"><span class="badge badge-info">140</span> The Effect of Motivational Postures as a Concomitant Factor and Peer Reporting Behavior on Taxpayer Compliance Decisions</h5> <div class="card-body"> <p class="card-text"><strong>Authors:</strong> <a href="https://publications.waset.org/abstracts/search?q=Elen%20Puspitasari">Elen Puspitasari</a>, <a href="https://publications.waset.org/abstracts/search?q=Yeye%20Susilowati"> Yeye Susilowati</a>, <a href="https://publications.waset.org/abstracts/search?q=Wahyu%20Meiranto"> Wahyu Meiranto</a> </p> <p class="card-text"><strong>Abstract:</strong></p> This study uses an experiment to examine the effect of motivational postures and peer’s reporting behavior on taxpayer compliance decisions. The motivational postures of taxpayers placed as a concomitant variable. Taxpayers were randomly assigned to alternate peer reporting behavior as an experimental variable with two level treatments and then responded to tax reporting scenarios. A motivational posture was measured with 29 statements developed by Braithwaite. Therefore, this experimental research uses Quasi-Experimental Design Between-Subject with Covariate with random assignment method. The subject in this experiment is the taxpayers who has a tax ID and have experience in reporting their tax revenue. The most important is that they earn income from their own business. The analysis technique used was Analysis of Covariate. The results showed that the posture of motivation as concomitant factors does not affect tax compliance decisions. Furthermore, this study proves that peer reporting behavior will determine the decisions of tax compliance. The findings in this study are intended to provide some practical implications for improving tax compliance. <p class="card-text"><strong>Keywords:</strong> <a href="https://publications.waset.org/abstracts/search?q=motivational%20postures" title="motivational postures">motivational postures</a>, <a href="https://publications.waset.org/abstracts/search?q=concomitant" title=" concomitant"> concomitant</a>, <a href="https://publications.waset.org/abstracts/search?q=tax%20compliance%20decisions" title=" tax compliance decisions"> tax compliance decisions</a>, <a href="https://publications.waset.org/abstracts/search?q=peer%20reporting%20behavior" title=" peer reporting behavior"> peer reporting behavior</a> </p> <a href="https://publications.waset.org/abstracts/30853/the-effect-of-motivational-postures-as-a-concomitant-factor-and-peer-reporting-behavior-on-taxpayer-compliance-decisions" class="btn btn-primary btn-sm">Procedia</a> <a href="https://publications.waset.org/abstracts/30853.pdf" target="_blank" class="btn btn-primary btn-sm">PDF</a> <span class="bg-info text-light px-1 py-1 float-right rounded"> Downloads <span class="badge badge-light">274</span> </span> </div> </div> <div class="card paper-listing mb-3 mt-3"> <h5 class="card-header" style="font-size:.9rem"><span class="badge badge-info">139</span> Measurement Errors and Misclassifications in Covariates in Logistic Regression: Bayesian Adjustment of Main and Interaction Effects and the Sample Size Implications</h5> <div class="card-body"> <p class="card-text"><strong>Authors:</strong> <a href="https://publications.waset.org/abstracts/search?q=Shahadut%20Hossain">Shahadut Hossain</a> </p> <p class="card-text"><strong>Abstract:</strong></p> Measurement errors in continuous covariates and/or misclassifications in categorical covariates are common in epidemiological studies. Regression analysis ignoring such mismeasurements seriously biases the estimated main and interaction effects of covariates on the outcome of interest. Thus, adjustments for such mismeasurements are necessary. In this research, we propose a Bayesian parametric framework for eliminating deleterious impacts of covariate mismeasurements in logistic regression. The proposed adjustment method is unified and thus can be applied to any generalized linear and non-linear regression models. Furthermore, adjustment for covariate mismeasurements requires validation data usually in the form of either gold standard measurements or replicates of the mismeasured covariates on a subset of the study population. Initial investigation shows that adequacy of such adjustment depends on the sizes of main and validation samples, especially when prevalences of the categorical covariates are low. Thus, we investigate the impact of main and validation sample sizes on the adjusted estimates, and provide a general guideline about these sample sizes based on simulation studies. <p class="card-text"><strong>Keywords:</strong> <a href="https://publications.waset.org/abstracts/search?q=measurement%20errors" title="measurement errors">measurement errors</a>, <a href="https://publications.waset.org/abstracts/search?q=misclassification" title=" misclassification"> misclassification</a>, <a href="https://publications.waset.org/abstracts/search?q=mismeasurement" title=" mismeasurement"> mismeasurement</a>, <a href="https://publications.waset.org/abstracts/search?q=validation%20sample" title=" validation sample"> validation sample</a>, <a href="https://publications.waset.org/abstracts/search?q=Bayesian%20adjustment" title=" Bayesian adjustment"> Bayesian adjustment</a> </p> <a href="https://publications.waset.org/abstracts/5349/measurement-errors-and-misclassifications-in-covariates-in-logistic-regression-bayesian-adjustment-of-main-and-interaction-effects-and-the-sample-size-implications" class="btn btn-primary btn-sm">Procedia</a> <a href="https://publications.waset.org/abstracts/5349.pdf" target="_blank" class="btn btn-primary btn-sm">PDF</a> <span class="bg-info text-light px-1 py-1 float-right rounded"> Downloads <span class="badge badge-light">408</span> </span> </div> </div> <div class="card paper-listing mb-3 mt-3"> <h5 class="card-header" style="font-size:.9rem"><span class="badge badge-info">138</span> The Effect of Mood and Normative Conformity on Prosocial Behavior</h5> <div class="card-body"> <p class="card-text"><strong>Authors:</strong> <a href="https://publications.waset.org/abstracts/search?q=Antoine%20Miguel%20Borromeo">Antoine Miguel Borromeo</a>, <a href="https://publications.waset.org/abstracts/search?q=Kristian%20Anthony%20Menez"> Kristian Anthony Menez</a>, <a href="https://publications.waset.org/abstracts/search?q=Moira%20Louise%20Ordonez"> Moira Louise Ordonez</a>, <a href="https://publications.waset.org/abstracts/search?q=David%20Carl%20Rabaya"> David Carl Rabaya</a> </p> <p class="card-text"><strong>Abstract:</strong></p> This study aimed to test if induced mood and normative conformity have any effect specifically on prosocial behavior, which was operationalized as the willingness to donate to a non-government organization. The effect of current attitude towards the object of the prosocial behavior was also considered with a covariate test. Undergraduates taking an introductory course on psychology (N = 132) from the University of the Philippines Diliman were asked how much money they were willing to donate after being presented a video about coral reef destruction and a website that advocates towards saving the coral reefs. A 3 (Induced mood: Positive vs Fear and Sadness vs Anger, Contempt, and Disgust) x 2 (Normative conformity: Presence vs Absence) between-subjects analysis of covariance was used for experimentation. Prosocial behavior was measured by presenting a circumstance wherein participants were given money and asked if they were willing to donate an amount to the non-government organization. An analysis of covariance revealed that the mood induced has no significant effect on prosocial behavior, F(2,125) = 0.654, p > 0.05. The analysis also showed how normative conformity has no significant effect on prosocial behavior, F(1,125) = 0.238, p > 0.05, as well as their interaction F(2, 125) = 1.580, p > 0.05. However, the covariate, current attitude towards corals was revealed to be significant, F(1,125) = 8.778, p < 0.05. From this, we speculate that inherent attitudes of people have a greater effect on prosocial behavior than temporary factors such as mood and conformity. <p class="card-text"><strong>Keywords:</strong> <a href="https://publications.waset.org/abstracts/search?q=attitude" title="attitude">attitude</a>, <a href="https://publications.waset.org/abstracts/search?q=induced%20mood" title=" induced mood"> induced mood</a>, <a href="https://publications.waset.org/abstracts/search?q=normative%20conformity" title=" normative conformity"> normative conformity</a>, <a href="https://publications.waset.org/abstracts/search?q=prosocial%20behavior" title=" prosocial behavior"> prosocial behavior</a> </p> <a href="https://publications.waset.org/abstracts/92777/the-effect-of-mood-and-normative-conformity-on-prosocial-behavior" class="btn btn-primary btn-sm">Procedia</a> <a href="https://publications.waset.org/abstracts/92777.pdf" target="_blank" class="btn btn-primary btn-sm">PDF</a> <span class="bg-info text-light px-1 py-1 float-right rounded"> Downloads <span class="badge badge-light">228</span> </span> </div> </div> <div class="card paper-listing mb-3 mt-3"> <h5 class="card-header" style="font-size:.9rem"><span class="badge badge-info">137</span> Group Sequential Covariate-Adjusted Response Adaptive Designs for Survival Outcomes</h5> <div class="card-body"> <p class="card-text"><strong>Authors:</strong> <a href="https://publications.waset.org/abstracts/search?q=Yaxian%20Chen">Yaxian Chen</a>, <a href="https://publications.waset.org/abstracts/search?q=Yeonhee%20Park"> Yeonhee Park</a> </p> <p class="card-text"><strong>Abstract:</strong></p> Driven by evolving FDA recommendations, modern clinical trials demand innovative designs that strike a balance between statistical rigor and ethical considerations. Covariate-adjusted response-adaptive (CARA) designs bridge this gap by utilizing patient attributes and responses to skew treatment allocation in favor of the treatment that is best for an individual patient’s profile. However, existing CARA designs for survival outcomes often hinge on specific parametric models, constraining their applicability in clinical practice. In this article, we address this limitation by introducing a CARA design for survival outcomes (CARAS) based on the Cox model and a variance estimator. This method addresses issues of model misspecification and enhances the flexibility of the design. We also propose a group sequential overlapweighted log-rank test to preserve type I error rate in the context of group sequential trials using extensive simulation studies to demonstrate the clinical benefit, statistical efficiency, and robustness to model misspecification of the proposed method compared to traditional randomized controlled trial designs and response-adaptive randomization designs. <p class="card-text"><strong>Keywords:</strong> <a href="https://publications.waset.org/abstracts/search?q=cox%20model" title="cox model">cox model</a>, <a href="https://publications.waset.org/abstracts/search?q=log-rank%20test" title=" log-rank test"> log-rank test</a>, <a href="https://publications.waset.org/abstracts/search?q=optimal%20allocation%20ratio" title=" optimal allocation ratio"> optimal allocation ratio</a>, <a href="https://publications.waset.org/abstracts/search?q=overlap%20weight" title=" overlap weight"> overlap weight</a>, <a href="https://publications.waset.org/abstracts/search?q=survival%20outcome" title=" survival outcome"> survival outcome</a> </p> <a href="https://publications.waset.org/abstracts/183302/group-sequential-covariate-adjusted-response-adaptive-designs-for-survival-outcomes" class="btn btn-primary btn-sm">Procedia</a> <a href="https://publications.waset.org/abstracts/183302.pdf" target="_blank" class="btn btn-primary btn-sm">PDF</a> <span class="bg-info text-light px-1 py-1 float-right rounded"> Downloads <span class="badge badge-light">64</span> </span> </div> </div> <div class="card paper-listing mb-3 mt-3"> <h5 class="card-header" style="font-size:.9rem"><span class="badge badge-info">136</span> Redefining the Croatian Economic Sentiment Indicator</h5> <div class="card-body"> <p class="card-text"><strong>Authors:</strong> <a href="https://publications.waset.org/abstracts/search?q=Ivana%20Lolic">Ivana Lolic</a>, <a href="https://publications.waset.org/abstracts/search?q=Petar%20Soric"> Petar Soric</a>, <a href="https://publications.waset.org/abstracts/search?q=Mirjana%20Cizmesija"> Mirjana Cizmesija</a> </p> <p class="card-text"><strong>Abstract:</strong></p> Based on Business and Consumer Survey (BCS) data, the European Commission (EC) regularly publishes the monthly Economic Sentiment Indicator (ESI) for each EU member state. ESI is conceptualized as a leading indicator, aimed ad tracking the overall economic activity. In calculating ESI, the EC employs arbitrarily chosen weights on 15 BCS response balances. This paper raises the predictive quality of ESI by applying nonlinear programming to find such weights that maximize the correlation coefficient of ESI and year-on-year GDP growth. The obtained results show that the highest weights are assigned to the response balances of industrial sector questions, followed by questions from the retail trade sector. This comes as no surprise since the existing literature shows that the industrial production is a plausible proxy for the overall Croatian economic activity and since Croatian GDP is largely influenced by the aggregate personal consumption. <p class="card-text"><strong>Keywords:</strong> <a href="https://publications.waset.org/abstracts/search?q=business%20and%20consumer%20survey" title="business and consumer survey">business and consumer survey</a>, <a href="https://publications.waset.org/abstracts/search?q=economic%20sentiment%20indicator" title=" economic sentiment indicator"> economic sentiment indicator</a>, <a href="https://publications.waset.org/abstracts/search?q=leading%20indicator" title=" leading indicator"> leading indicator</a>, <a href="https://publications.waset.org/abstracts/search?q=nonlinear%20optimization%20with%20constraints" title=" nonlinear optimization with constraints"> nonlinear optimization with constraints</a> </p> <a href="https://publications.waset.org/abstracts/27350/redefining-the-croatian-economic-sentiment-indicator" class="btn btn-primary btn-sm">Procedia</a> <a href="https://publications.waset.org/abstracts/27350.pdf" target="_blank" class="btn btn-primary btn-sm">PDF</a> <span class="bg-info text-light px-1 py-1 float-right rounded"> Downloads <span class="badge badge-light">462</span> </span> </div> </div> <div class="card paper-listing mb-3 mt-3"> <h5 class="card-header" style="font-size:.9rem"><span class="badge badge-info">135</span> Effectiveness of Weather Index Insurance for Smallholders in Ethiopia</h5> <div class="card-body"> <p class="card-text"><strong>Authors:</strong> <a href="https://publications.waset.org/abstracts/search?q=Federica%20Di%20Marcantonio">Federica Di Marcantonio</a>, <a href="https://publications.waset.org/abstracts/search?q=Antoine%20Leblois"> Antoine Leblois</a>, <a href="https://publications.waset.org/abstracts/search?q=Wolfgang%20G%C3%B6bel"> Wolfgang Göbel</a>, <a href="https://publications.waset.org/abstracts/search?q=Herv%C3%A8%20Kerdiles"> Hervè Kerdiles</a> </p> <p class="card-text"><strong>Abstract:</strong></p> Weather-related shocks can threaten the ability of farmers to maintain their agricultural output and food security levels. Informal coping mechanisms (i.e. migration or community risk sharing) have always played a significant role in mitigating the negative effects of weather-related shocks in Ethiopia, but they have been found to be an incomplete strategy, particularly as a response to covariate shocks. Particularly, as an alternative to the traditional risk pooling products, an innovative form of insurance known as Index-based Insurance has received a lot of attention from researchers and international organizations, leading to an increased number of pilot initiatives in many countries. Despite the potential benefit of the product in protecting the livelihoods of farmers and pastoralists against climate shocks, to date there has been an unexpectedly low uptake. Using information from current pilot projects on index-based insurance in Ethiopia, this paper discusses the determinants of uptake that have so far undermined the scaling-up of the products, by focusing in particular on weather data availability, price affordability and willingness to pay. We found that, aside from data constraint issues, high price elasticity and low willingness to pay represent impediments to the development of the market. These results, bring us to rethink the role of index insurance as products for enhancing smallholders’ response to covariate shocks, and particularly for improving their food security. <p class="card-text"><strong>Keywords:</strong> <a href="https://publications.waset.org/abstracts/search?q=index-based%20insurance" title="index-based insurance">index-based insurance</a>, <a href="https://publications.waset.org/abstracts/search?q=willingness%20to%20pay" title=" willingness to pay"> willingness to pay</a>, <a href="https://publications.waset.org/abstracts/search?q=satellite%20information" title=" satellite information"> satellite information</a>, <a href="https://publications.waset.org/abstracts/search?q=Ethiopia" title=" Ethiopia"> Ethiopia</a> </p> <a href="https://publications.waset.org/abstracts/40493/effectiveness-of-weather-index-insurance-for-smallholders-in-ethiopia" class="btn btn-primary btn-sm">Procedia</a> <a href="https://publications.waset.org/abstracts/40493.pdf" target="_blank" class="btn btn-primary btn-sm">PDF</a> <span class="bg-info text-light px-1 py-1 float-right rounded"> Downloads <span class="badge badge-light">405</span> </span> </div> </div> <div class="card paper-listing mb-3 mt-3"> <h5 class="card-header" style="font-size:.9rem"><span class="badge badge-info">134</span> The Success and Failure of the Solicitor General When the U.S. Government Appears as a Direct Party before the U.S. Supreme Court</h5> <div class="card-body"> <p class="card-text"><strong>Authors:</strong> <a href="https://publications.waset.org/abstracts/search?q=Joseph%20Ignagni">Joseph Ignagni</a>, <a href="https://publications.waset.org/abstracts/search?q=Rebecca%20Deen"> Rebecca Deen</a> </p> <p class="card-text"><strong>Abstract:</strong></p> This paper analyzes the extent to which the U.S. Supreme Court votes to support the position of the United States in cases where the government is a party to the litigation. This study considers the relationship between the Solicitor General’s Office and the U.S. Supreme Court. The Solicitor General has the unique position of being the representative of the Executive Branch and the U.S. government before the Supreme Court. While a great deal of research has looked at the Solicitor General’s success as a “friend of the court,” far less has considered this relationship when the U.S. is a direct party in the litigation. This paper investigates the success rate of the Solicitor General’s Office in these cases. We find that there is considerable variation in the U.S. government’s success rate before the Court depending on the issue, Supreme Court leadership, the ideological direction of the Court and whether the U.S. approached the Court as a petitioner or respondent. We conduct our analysis on the Court’s decisions from 1953-2009. This study adds to our understanding of checks and balances, separation of powers, and inter-institutional relationships between the branches of the federal government of the United States. <p class="card-text"><strong>Keywords:</strong> <a href="https://publications.waset.org/abstracts/search?q=U.S.%20president" title="U.S. president">U.S. president</a>, <a href="https://publications.waset.org/abstracts/search?q=solicitor%20general" title=" solicitor general"> solicitor general</a>, <a href="https://publications.waset.org/abstracts/search?q=U.S.%20Supreme%20Court" title=" U.S. Supreme Court"> U.S. Supreme Court</a>, <a href="https://publications.waset.org/abstracts/search?q=separation%20of%20power" title=" separation of power"> separation of power</a>, <a href="https://publications.waset.org/abstracts/search?q=checks%20and%20balances" title=" checks and balances"> checks and balances</a> </p> <a href="https://publications.waset.org/abstracts/3984/the-success-and-failure-of-the-solicitor-general-when-the-us-government-appears-as-a-direct-party-before-the-us-supreme-court" class="btn btn-primary btn-sm">Procedia</a> <a href="https://publications.waset.org/abstracts/3984.pdf" target="_blank" class="btn btn-primary btn-sm">PDF</a> <span class="bg-info text-light px-1 py-1 float-right rounded"> Downloads <span class="badge badge-light">360</span> </span> </div> </div> <div class="card paper-listing mb-3 mt-3"> <h5 class="card-header" style="font-size:.9rem"><span class="badge badge-info">133</span> Analysis on Financial Status and Operational Performance of Suan Sunandha Rajabhat University in 3 Fiscal Years (2011-2013)</h5> <div class="card-body"> <p class="card-text"><strong>Authors:</strong> <a href="https://publications.waset.org/abstracts/search?q=Anocha%20Kimkong">Anocha Kimkong</a>, <a href="https://publications.waset.org/abstracts/search?q=Natnichar%20Kleebbuabarn"> Natnichar Kleebbuabarn</a> </p> <p class="card-text"><strong>Abstract:</strong></p> This research work has the objective to analyze the financial status and operational performance of Suan Sunandha Rajabhat University (SSRU) in 3 fiscal years (2011-2013). The tool used is a form to record financial statements and balances of the university. The analysis is based on the calculation that regards the figures in the fiscal year of 2011 as the 100% bases to be compared with the same figures in the fiscal years of 2012 and 2013, which are multiplied by 100 and divided by the base figures. The outcomes are the percentages of each year, which can reflect the rising, stable, and falling trends. The results from the analysis reveal that SSRU’s financial status is getting better because the gross assets, debts and accumulated cash are increasing in the fiscal years of 2012 and 2013. Concerning the operational performance, the university’s incomes and expenses are rising from the fiscal year of 2011. This makes the university’s incomes grow higher than expenses. <p class="card-text"><strong>Keywords:</strong> <a href="https://publications.waset.org/abstracts/search?q=financial%20status" title="financial status">financial status</a>, <a href="https://publications.waset.org/abstracts/search?q=operational%20performance" title=" operational performance"> operational performance</a>, <a href="https://publications.waset.org/abstracts/search?q=Suan%20Sunandha%20Rajabhat%20University" title=" Suan Sunandha Rajabhat University"> Suan Sunandha Rajabhat University</a>, <a href="https://publications.waset.org/abstracts/search?q=balances" title=" balances"> balances</a> </p> <a href="https://publications.waset.org/abstracts/11982/analysis-on-financial-status-and-operational-performance-of-suan-sunandha-rajabhat-university-in-3-fiscal-years-2011-2013" class="btn btn-primary btn-sm">Procedia</a> <a href="https://publications.waset.org/abstracts/11982.pdf" target="_blank" class="btn btn-primary btn-sm">PDF</a> <span class="bg-info text-light px-1 py-1 float-right rounded"> Downloads <span class="badge badge-light">382</span> </span> </div> </div> <div class="card paper-listing mb-3 mt-3"> <h5 class="card-header" style="font-size:.9rem"><span class="badge badge-info">132</span> Juxtaposing Constitutionalism and Democratic Process in Nigeria Vis a Vis the South African Perspective</h5> <div class="card-body"> <p class="card-text"><strong>Authors:</strong> <a href="https://publications.waset.org/abstracts/search?q=Onyinyechi%20Lilian%20Uche">Onyinyechi Lilian Uche</a> </p> <p class="card-text"><strong>Abstract:</strong></p> Limiting arbitrariness and political power in governance is expressed in the concept of constitutionalism. Constitutionalism acknowledges the necessity for government but insists upon a limitation being placed upon its powers. It is therefore clear that the essence of constitutionalism is obviation of arbitrariness in governance and maximisation of liberty with adequate and expedient restraint on government. The doctrine of separation of powers accompanied by a system of checks and balances in Nigeria like many other African countries is marked by elements of ‘personal government’ and this has raised questions about whether the apparent separation of powers provided for in the Nigerian Constitution is not just a euphemism for the hegemony of the executive over the other two arms of government; the legislature and the judiciary. Another question raised in the article is whether the doctrine is merely an abstract philosophical inheritance that lacks both content and relevance to the realities of the country and region today? The current happenings in Nigeria and most African countries such as the flagrant disregard of court orders by the Executive, indicate clearly that the concept constitutionalism ordinarily goes beyond mere form and strikes at the substance of a constitution. It, therefore, involves a consideration of whether there are provisions in the constitution which limit arbitrariness in the exercise of political powers by providing checks and balances upon such exercise. These questions underscore the need for Africa to craft its own understanding of the separation of powers between the arms of government in furtherance of good governance as it has been seen that it is possible to have a constitution in place which may just be a mere statement of unenforceable ‘rights’ or may be bereft of provisions guaranteeing liberty or adequate and necessary restraint on exercise of government. This paper seeks to expatiate on the importance of the nexus between constitutionalism and democratic process and a juxtaposition of practices between Nigeria and South Africa. The article notes that an abstract analysis of constitutionalism without recourse to the democratic process is meaningless and also analyses the structure of government of some selected African countries. These are examined the extent to which the doctrine operates within the arms of government and concludes that it should not just be regarded as a general constitutional principle but made rigid or perhaps effective and binding through law and institutional reforms. <p class="card-text"><strong>Keywords:</strong> <a href="https://publications.waset.org/abstracts/search?q=checks%20and%20balances" title="checks and balances">checks and balances</a>, <a href="https://publications.waset.org/abstracts/search?q=constitutionalism" title=" constitutionalism"> constitutionalism</a>, <a href="https://publications.waset.org/abstracts/search?q=democratic%20process" title=" democratic process"> democratic process</a>, <a href="https://publications.waset.org/abstracts/search?q=separation%20of%20power" title=" separation of power"> separation of power</a> </p> <a href="https://publications.waset.org/abstracts/82772/juxtaposing-constitutionalism-and-democratic-process-in-nigeria-vis-a-vis-the-south-african-perspective" class="btn btn-primary btn-sm">Procedia</a> <a href="https://publications.waset.org/abstracts/82772.pdf" target="_blank" class="btn btn-primary btn-sm">PDF</a> <span class="bg-info text-light px-1 py-1 float-right rounded"> Downloads <span class="badge badge-light">125</span> </span> </div> </div> <div class="card paper-listing mb-3 mt-3"> <h5 class="card-header" style="font-size:.9rem"><span class="badge badge-info">131</span> Diabetes Mellitus and Food Balance in the Kingdom of Saudi Arabia</h5> <div class="card-body"> <p class="card-text"><strong>Authors:</strong> <a href="https://publications.waset.org/abstracts/search?q=Aljabryn%20Dalal%20Hamad">Aljabryn Dalal Hamad</a> </p> <p class="card-text"><strong>Abstract:</strong></p> The present explanatory study concerns with the relation between Diabetes Mellitus and Food Balance in the Kingdom of Saudi Arabia during 2005-2010, using published data. Results illustrated that Saudi citizen daily protein consumption (DPC) during 2005-2007 (g/capita/day) is higher than the average global consumption level of protein with 15.27%, daily fat consumption (DFC) with 24.56% and daily energy consumption (DEC) with 16.93% and increases than recommended level by International Nutrition Organizations (INO) with 56% for protein, 60.49% for fat and 27.37% for energy. On the other hand, DPC per capita in Saudi Arabia decreased during the period 2008-2010 from 88.3 to 82.36 gram/ day. Moreover, DFC per capita in Saudi Arabia decreased during the period 2008-2010 from 3247.90 to 3176.43 Cal/capita/ day, and daily energy consumption (DEC) of Saudi citizen increases than world consumption with 16.93%, while increases with 27.37% than INO. Despite this, DPC, DFC and DEC per capita in Saudi Arabia still higher than world mean. On the other side, results illustrated that the number of diabetic patients in Saudi Arabia during the same period (2005-2010). The curve of diabetic patient’s number in Saudi Arabia during 2005-2010 is regular ascending with increasing level ranged between 7.10% in 2005 and 12.44% in 2010. It is essential to devise Saudi National programs to educate the public about the relation of food balances and diabetes so it could be avoided, and provide citizens with healthy dietary balances tables. <p class="card-text"><strong>Keywords:</strong> <a href="https://publications.waset.org/abstracts/search?q=Diabetes%20mellitus" title="Diabetes mellitus">Diabetes mellitus</a>, <a href="https://publications.waset.org/abstracts/search?q=food%20balance" title=" food balance"> food balance</a>, <a href="https://publications.waset.org/abstracts/search?q=energy" title=" energy"> energy</a>, <a href="https://publications.waset.org/abstracts/search?q=fat" title=" fat"> fat</a>, <a href="https://publications.waset.org/abstracts/search?q=protein" title=" protein"> protein</a>, <a href="https://publications.waset.org/abstracts/search?q=Saudi%20Arabia" title=" Saudi Arabia"> Saudi Arabia</a> </p> <a href="https://publications.waset.org/abstracts/30259/diabetes-mellitus-and-food-balance-in-the-kingdom-of-saudi-arabia" class="btn btn-primary btn-sm">Procedia</a> <a href="https://publications.waset.org/abstracts/30259.pdf" target="_blank" class="btn btn-primary btn-sm">PDF</a> <span class="bg-info text-light px-1 py-1 float-right rounded"> Downloads <span class="badge badge-light">460</span> </span> </div> </div> <div class="card paper-listing mb-3 mt-3"> <h5 class="card-header" style="font-size:.9rem"><span class="badge badge-info">130</span> Agroforestry Systems: A Sustainable Strategy of the Agricultural Systems of Cumaral (Meta), Colombia</h5> <div class="card-body"> <p class="card-text"><strong>Authors:</strong> <a href="https://publications.waset.org/abstracts/search?q=Amanda%20Silva%20Parra">Amanda Silva Parra</a>, <a href="https://publications.waset.org/abstracts/search?q=Dayra%20Yisel%20Garc%C3%ADa%20Ramirez"> Dayra Yisel García Ramirez</a> </p> <p class="card-text"><strong>Abstract:</strong></p> In developing countries, agricultural "modernization" has led to a loss of biodiversity and inefficiency of agricultural systems, manifested in increases in Greenhouse Gas Emissions (GHG) and the C footprint, generating the susceptibility of systems agriculture to environmental problems, loss of biodiversity, depletion of natural resources, soil degradation and loss of nutrients, and a decrease in the supply of products that affect food security for peoples and nations. Each year agriculture emits 10 to 12% (5.1 to 6.1 Gt CO2eq per year) of the total estimated GHG emissions (51 Gt CO2 eq per year). The FAO recommends that countries that have not yet done so consider declaring sustainable agriculture as an essential or strategic activity of public interest within the framework of green economies to better face global climate change. The objective of this research was to estimate the balance of GHG in agricultural systems of Cumaral, Meta (Colombia), to contribute to the recovery and sustainable operation of agricultural systems that guarantee food security and face changes generated by the climate in a more intelligent way. To determine the GHG balances, the IPCC methodologies were applied with a Tier 1 and 2 level of use. It was estimated that all the silvopastoral systems evaluated play an important role in this reconversion compared to conventional systems such as improved pastures. and degraded pastures due to their ability to capture C both in soil and in biomass, generating positive GHG balances, guaranteeing greater sustainability of soil and air resources. <p class="card-text"><strong>Keywords:</strong> <a href="https://publications.waset.org/abstracts/search?q=climate%20change" title="climate change">climate change</a>, <a href="https://publications.waset.org/abstracts/search?q=carbon%20capture" title=" carbon capture"> carbon capture</a>, <a href="https://publications.waset.org/abstracts/search?q=environmental%20sustainability" title=" environmental sustainability"> environmental sustainability</a>, <a href="https://publications.waset.org/abstracts/search?q=GHG%20mitigation" title=" GHG mitigation"> GHG mitigation</a>, <a href="https://publications.waset.org/abstracts/search?q=silvopastoral%20systems" title=" silvopastoral systems"> silvopastoral systems</a> </p> <a href="https://publications.waset.org/abstracts/147182/agroforestry-systems-a-sustainable-strategy-of-the-agricultural-systems-of-cumaral-meta-colombia" class="btn btn-primary btn-sm">Procedia</a> <a href="https://publications.waset.org/abstracts/147182.pdf" target="_blank" class="btn btn-primary btn-sm">PDF</a> <span class="bg-info text-light px-1 py-1 float-right rounded"> Downloads <span class="badge badge-light">118</span> </span> </div> </div> <div class="card paper-listing mb-3 mt-3"> <h5 class="card-header" style="font-size:.9rem"><span class="badge badge-info">129</span> Causal Estimation for the Left-Truncation Adjusted Time-Varying Covariates under the Semiparametric Transformation Models of a Survival Time</h5> <div class="card-body"> <p class="card-text"><strong>Authors:</strong> <a href="https://publications.waset.org/abstracts/search?q=Yemane%20Hailu%20Fissuh">Yemane Hailu Fissuh</a>, <a href="https://publications.waset.org/abstracts/search?q=Zhongzhan%20Zhang"> Zhongzhan Zhang</a> </p> <p class="card-text"><strong>Abstract:</strong></p> In biomedical researches and randomized clinical trials, the most commonly interested outcomes are time-to-event so-called survival data. The importance of robust models in this context is to compare the effect of randomly controlled experimental groups that have a sense of causality. Causal estimation is the scientific concept of comparing the pragmatic effect of treatments conditional to the given covariates rather than assessing the simple association of response and predictors. Hence, the causal effect based semiparametric transformation model was proposed to estimate the effect of treatment with the presence of possibly time-varying covariates. Due to its high flexibility and robustness, the semiparametric transformation model which shall be applied in this paper has been given much more attention for estimation of a causal effect in modeling left-truncated and right censored survival data. Despite its wide applications and popularity in estimating unknown parameters, the maximum likelihood estimation technique is quite complex and burdensome in estimating unknown parameters and unspecified transformation function in the presence of possibly time-varying covariates. Thus, to ease the complexity we proposed the modified estimating equations. After intuitive estimation procedures, the consistency and asymptotic properties of the estimators were derived and the characteristics of the estimators in the finite sample performance of the proposed model were illustrated via simulation studies and Stanford heart transplant real data example. To sum up the study, the bias of covariates was adjusted via estimating the density function for truncation variable which was also incorporated in the model as a covariate in order to relax the independence assumption of failure time and truncation time. Moreover, the expectation-maximization (EM) algorithm was described for the estimation of iterative unknown parameters and unspecified transformation function. In addition, the causal effect was derived by the ratio of the cumulative hazard function of active and passive experiments after adjusting for bias raised in the model due to the truncation variable. <p class="card-text"><strong>Keywords:</strong> <a href="https://publications.waset.org/abstracts/search?q=causal%20estimation" title="causal estimation">causal estimation</a>, <a href="https://publications.waset.org/abstracts/search?q=EM%20algorithm" title=" EM algorithm"> EM algorithm</a>, <a href="https://publications.waset.org/abstracts/search?q=semiparametric%20transformation%20models" title=" semiparametric transformation models"> semiparametric transformation models</a>, <a href="https://publications.waset.org/abstracts/search?q=time-to-event%20outcomes" title=" time-to-event outcomes"> time-to-event outcomes</a>, <a href="https://publications.waset.org/abstracts/search?q=time-varying%20covariate" title=" time-varying covariate "> time-varying covariate </a> </p> <a href="https://publications.waset.org/abstracts/107145/causal-estimation-for-the-left-truncation-adjusted-time-varying-covariates-under-the-semiparametric-transformation-models-of-a-survival-time" class="btn btn-primary btn-sm">Procedia</a> <a href="https://publications.waset.org/abstracts/107145.pdf" target="_blank" class="btn btn-primary btn-sm">PDF</a> <span class="bg-info text-light px-1 py-1 float-right rounded"> Downloads <span class="badge badge-light">125</span> </span> </div> </div> <div class="card paper-listing mb-3 mt-3"> <h5 class="card-header" style="font-size:.9rem"><span class="badge badge-info">128</span> A Modified Estimating Equations in Derivation of the Causal Effect on the Survival Time with Time-Varying Covariates</h5> <div class="card-body"> <p class="card-text"><strong>Authors:</strong> <a href="https://publications.waset.org/abstracts/search?q=Yemane%20Hailu%20Fissuh">Yemane Hailu Fissuh</a>, <a href="https://publications.waset.org/abstracts/search?q=Zhongzhan%20Zhang"> Zhongzhan Zhang</a> </p> <p class="card-text"><strong>Abstract:</strong></p> a systematic observation from a defined time of origin up to certain failure or censor is known as survival data. Survival analysis is a major area of interest in biostatistics and biomedical researches. At the heart of understanding, the most scientific and medical research inquiries lie for a causality analysis. Thus, the main concern of this study is to investigate the causal effect of treatment on survival time conditional to the possibly time-varying covariates. The theory of causality often differs from the simple association between the response variable and predictors. A causal estimation is a scientific concept to compare a pragmatic effect between two or more experimental arms. To evaluate an average treatment effect on survival outcome, the estimating equation was adjusted for time-varying covariates under the semi-parametric transformation models. The proposed model intuitively obtained the consistent estimators for unknown parameters and unspecified monotone transformation functions. In this article, the proposed method estimated an unbiased average causal effect of treatment on survival time of interest. The modified estimating equations of semiparametric transformation models have the advantage to include the time-varying effect in the model. Finally, the finite sample performance characteristics of the estimators proved through the simulation and Stanford heart transplant real data. To this end, the average effect of a treatment on survival time estimated after adjusting for biases raised due to the high correlation of the left-truncation and possibly time-varying covariates. The bias in covariates was restored, by estimating density function for left-truncation. Besides, to relax the independence assumption between failure time and truncation time, the model incorporated the left-truncation variable as a covariate. Moreover, the expectation-maximization (EM) algorithm iteratively obtained unknown parameters and unspecified monotone transformation functions. To summarize idea, the ratio of cumulative hazards functions between the treated and untreated experimental group has a sense of the average causal effect for the entire population. <p class="card-text"><strong>Keywords:</strong> <a href="https://publications.waset.org/abstracts/search?q=a%20modified%20estimation%20equation" title="a modified estimation equation">a modified estimation equation</a>, <a href="https://publications.waset.org/abstracts/search?q=causal%20effect" title=" causal effect"> causal effect</a>, <a href="https://publications.waset.org/abstracts/search?q=semiparametric%20transformation%20models" title=" semiparametric transformation models"> semiparametric transformation models</a>, <a href="https://publications.waset.org/abstracts/search?q=survival%20analysis" title=" survival analysis"> survival analysis</a>, <a href="https://publications.waset.org/abstracts/search?q=time-varying%20covariate" title=" time-varying covariate"> time-varying covariate</a> </p> <a href="https://publications.waset.org/abstracts/107135/a-modified-estimating-equations-in-derivation-of-the-causal-effect-on-the-survival-time-with-time-varying-covariates" class="btn btn-primary btn-sm">Procedia</a> <a href="https://publications.waset.org/abstracts/107135.pdf" target="_blank" class="btn btn-primary btn-sm">PDF</a> <span class="bg-info text-light px-1 py-1 float-right rounded"> Downloads <span class="badge badge-light">175</span> </span> </div> </div> <div class="card paper-listing mb-3 mt-3"> <h5 class="card-header" style="font-size:.9rem"><span class="badge badge-info">127</span> Survival Data with Incomplete Missing Categorical Covariates</h5> <div class="card-body"> <p class="card-text"><strong>Authors:</strong> <a href="https://publications.waset.org/abstracts/search?q=Madaki%20Umar%20Yusuf">Madaki Umar Yusuf</a>, <a href="https://publications.waset.org/abstracts/search?q=Mohd%20Rizam%20B.%20Abubakar"> Mohd Rizam B. Abubakar</a> </p> <p class="card-text"><strong>Abstract:</strong></p> The survival censored data with incomplete covariate data is a common occurrence in many studies in which the outcome is survival time. With model when the missing covariates are categorical, a useful technique for obtaining parameter estimates is the EM by the method of weights. The survival outcome for the class of generalized linear model is applied and this method requires the estimation of the parameters of the distribution of the covariates. In this paper, we propose some clinical trials with ve covariates, four of which have some missing values which clearly show that they were fully censored data. <p class="card-text"><strong>Keywords:</strong> <a href="https://publications.waset.org/abstracts/search?q=EM%20algorithm" title="EM algorithm">EM algorithm</a>, <a href="https://publications.waset.org/abstracts/search?q=incomplete%20categorical%20covariates" title=" incomplete categorical covariates"> incomplete categorical covariates</a>, <a href="https://publications.waset.org/abstracts/search?q=ignorable%20missing%20data" title=" ignorable missing data"> ignorable missing data</a>, <a href="https://publications.waset.org/abstracts/search?q=missing%20at%20random%20%28MAR%29" title=" missing at random (MAR)"> missing at random (MAR)</a>, <a href="https://publications.waset.org/abstracts/search?q=Weibull%20Distribution" title=" Weibull Distribution"> Weibull Distribution</a> </p> <a href="https://publications.waset.org/abstracts/43520/survival-data-with-incomplete-missing-categorical-covariates" class="btn btn-primary btn-sm">Procedia</a> <a href="https://publications.waset.org/abstracts/43520.pdf" target="_blank" class="btn btn-primary btn-sm">PDF</a> <span class="bg-info text-light px-1 py-1 float-right rounded"> Downloads <span class="badge badge-light">405</span> </span> </div> </div> <div class="card paper-listing mb-3 mt-3"> <h5 class="card-header" style="font-size:.9rem"><span class="badge badge-info">126</span> Constraints on IRS Control: An Alternative Approach to Tax Gap Analysis</h5> <div class="card-body"> <p class="card-text"><strong>Authors:</strong> <a href="https://publications.waset.org/abstracts/search?q=J.%20T.%20Manhire">J. T. Manhire</a> </p> <p class="card-text"><strong>Abstract:</strong></p> A tax authority wants to take actions it knows will foster the greatest degree of voluntary taxpayer compliance to reduce the “tax gap.” This paper suggests that even if a tax authority could attain a state of complete knowledge, there are constraints on whether and to what extent such actions would result in reducing the macro-level tax gap. These limits are not merely a consequence of finite agency resources. They are inherent in the system itself. To show that this is one possible interpretation of the tax gap data, the paper formulates known results in a different way by analyzing tax compliance as a population with a single covariate. This leads to a standard use of the logistic map to analyze the dynamics of non-compliance growth or decay over a sequence of periods. This formulation gives the same results as the tax gap studies performed over the past fifty years in the U.S. given the published margins of error. Limitations and recommendations for future work are discussed, along with some implications for tax policy. <p class="card-text"><strong>Keywords:</strong> <a href="https://publications.waset.org/abstracts/search?q=income%20tax" title="income tax">income tax</a>, <a href="https://publications.waset.org/abstracts/search?q=logistic%20map" title=" logistic map"> logistic map</a>, <a href="https://publications.waset.org/abstracts/search?q=tax%20compliance" title=" tax compliance"> tax compliance</a>, <a href="https://publications.waset.org/abstracts/search?q=tax%20law" title=" tax law"> tax law</a> </p> <a href="https://publications.waset.org/abstracts/96876/constraints-on-irs-control-an-alternative-approach-to-tax-gap-analysis" class="btn btn-primary btn-sm">Procedia</a> <a href="https://publications.waset.org/abstracts/96876.pdf" target="_blank" class="btn btn-primary btn-sm">PDF</a> <span class="bg-info text-light px-1 py-1 float-right rounded"> Downloads <span class="badge badge-light">120</span> </span> </div> </div> <div class="card paper-listing mb-3 mt-3"> <h5 class="card-header" style="font-size:.9rem"><span class="badge badge-info">125</span> Sustainable Refrigerated Transport Engineering</h5> <div class="card-body"> <p class="card-text"><strong>Authors:</strong> <a href="https://publications.waset.org/abstracts/search?q=A.%20A">A. A</a>, <a href="https://publications.waset.org/abstracts/search?q=F.%20Belmir"> F. Belmir</a>, <a href="https://publications.waset.org/abstracts/search?q=A.%20El%20Bouari"> A. El Bouari</a>, <a href="https://publications.waset.org/abstracts/search?q=Y.%20Abboud"> Y. Abboud</a> </p> <p class="card-text"><strong>Abstract:</strong></p> This article presents a study of the thermal performance of a new solar mobile refrigeration prototype for the preservation of perishable foods. The simulation of the refrigeration cycle and the calculation of the thermal balances made it possible to estimate its consumption and to evaluate the capacity of each photovoltaic component necessary for the production of energy. The study provides a description of the refrigerator construction and operation, including an energy balance analysis of the refrigerator performance under typical loads. The photovoltaic system requirements are also detailed. <p class="card-text"><strong>Keywords:</strong> <a href="https://publications.waset.org/abstracts/search?q=composite" title="composite">composite</a>, <a href="https://publications.waset.org/abstracts/search?q=material" title=" material"> material</a>, <a href="https://publications.waset.org/abstracts/search?q=photovoltaic" title=" photovoltaic"> photovoltaic</a>, <a href="https://publications.waset.org/abstracts/search?q=refrigeration" title=" refrigeration"> refrigeration</a>, <a href="https://publications.waset.org/abstracts/search?q=thermal" title=" thermal"> thermal</a> </p> <a href="https://publications.waset.org/abstracts/138620/sustainable-refrigerated-transport-engineering" class="btn btn-primary btn-sm">Procedia</a> <a href="https://publications.waset.org/abstracts/138620.pdf" target="_blank" class="btn btn-primary btn-sm">PDF</a> <span class="bg-info text-light px-1 py-1 float-right rounded"> Downloads <span class="badge badge-light">246</span> </span> </div> </div> <div class="card paper-listing mb-3 mt-3"> <h5 class="card-header" style="font-size:.9rem"><span class="badge badge-info">124</span> Italian Colonial Strategy in Libya and the Conflict of Super Powers</h5> <div class="card-body"> <p class="card-text"><strong>Authors:</strong> <a href="https://publications.waset.org/abstracts/search?q=Mohamed%20Basheer%20Abdul%20Atti%20Hassan">Mohamed Basheer Abdul Atti Hassan</a> </p> <p class="card-text"><strong>Abstract:</strong></p> This research paper will follow the main outlines of the Italian colonization in Libya in a historical geopolitical approach; before we reach the contemporary map. In this study, we are also concerned with following the chain's links, not as drama in time, but as a strategy in place, so that it draws to us a map of power and the distribution of political formations throughout this period within and around Libya. From the sum of these variable distributions and successive balances, we can come up with the basic principles that determined the Italian history in Libya and formed its political entity, which is a compass of guidance and an indication of the future. <p class="card-text"><strong>Keywords:</strong> <a href="https://publications.waset.org/abstracts/search?q=conflict" title="conflict">conflict</a>, <a href="https://publications.waset.org/abstracts/search?q=Mediterranean" title=" Mediterranean"> Mediterranean</a>, <a href="https://publications.waset.org/abstracts/search?q=colonization" title=" colonization"> colonization</a>, <a href="https://publications.waset.org/abstracts/search?q=political%20history" title=" political history"> political history</a> </p> <a href="https://publications.waset.org/abstracts/128380/italian-colonial-strategy-in-libya-and-the-conflict-of-super-powers" class="btn btn-primary btn-sm">Procedia</a> <a href="https://publications.waset.org/abstracts/128380.pdf" target="_blank" class="btn btn-primary btn-sm">PDF</a> <span class="bg-info text-light px-1 py-1 float-right rounded"> Downloads <span class="badge badge-light">160</span> </span> </div> </div> <div class="card paper-listing mb-3 mt-3"> <h5 class="card-header" style="font-size:.9rem"><span class="badge badge-info">123</span> Tests for Zero Inflation in Count Data with Measurement Error in Covariates</h5> <div class="card-body"> <p class="card-text"><strong>Authors:</strong> <a href="https://publications.waset.org/abstracts/search?q=Man-Yu%20Wong">Man-Yu Wong</a>, <a href="https://publications.waset.org/abstracts/search?q=Siyu%20Zhou"> Siyu Zhou</a>, <a href="https://publications.waset.org/abstracts/search?q=Zhiqiang%20Cao"> Zhiqiang Cao</a> </p> <p class="card-text"><strong>Abstract:</strong></p> In quality of life, health service utilization is an important determinant of medical resource expenditures on Colorectal cancer (CRC) care, a better understanding of the increased utilization of health services is essential for optimizing the allocation of healthcare resources to services and thus for enhancing the service quality, especially for high expenditure on CRC care like Hong Kong region. In assessing the association between the health-related quality of life (HRQOL) and health service utilization in patients with colorectal neoplasm, count data models can be used, which account for over dispersion or extra zero counts. In our data, the HRQOL evaluation is a self-reported measure obtained from a questionnaire completed by the patients, misreports and variations in the data are inevitable. Besides, there are more zero counts from the observed number of clinical consultations (observed frequency of zero counts = 206) than those from a Poisson distribution with mean equal to 1.33 (expected frequency of zero counts = 156). This suggests that excess of zero counts may exist. Therefore, we study tests for detecting zero-inflation in models with measurement error in covariates. Method: Under classical measurement error model, the approximate likelihood function for zero-inflation Poisson regression model can be obtained, then Approximate Maximum Likelihood Estimation(AMLE) can be derived accordingly, which is consistent and asymptotically normally distributed. By calculating score function and Fisher information based on AMLE, a score test is proposed to detect zero-inflation effect in ZIP model with measurement error. The proposed test follows asymptotically standard normal distribution under H0, and it is consistent with the test proposed for zero-inflation effect when there is no measurement error. Results: Simulation results show that empirical power of our proposed test is the highest among existing tests for zero-inflation in ZIP model with measurement error. In real data analysis, with or without considering measurement error in covariates, existing tests, and our proposed test all imply H0 should be rejected with P-value less than 0.001, i.e., zero-inflation effect is very significant, ZIP model is superior to Poisson model for analyzing this data. However, if measurement error in covariates is not considered, only one covariate is significant; if measurement error in covariates is considered, only another covariate is significant. Moreover, the direction of coefficient estimations for these two covariates is different in ZIP regression model with or without considering measurement error. Conclusion: In our study, compared to Poisson model, ZIP model should be chosen when assessing the association between condition-specific HRQOL and health service utilization in patients with colorectal neoplasm. and models taking measurement error into account will result in statistically more reliable and precise information. <p class="card-text"><strong>Keywords:</strong> <a href="https://publications.waset.org/abstracts/search?q=count%20data" title="count data">count data</a>, <a href="https://publications.waset.org/abstracts/search?q=measurement%20error" title=" measurement error"> measurement error</a>, <a href="https://publications.waset.org/abstracts/search?q=score%20test" title=" score test"> score test</a>, <a href="https://publications.waset.org/abstracts/search?q=zero%20inflation" title=" zero inflation"> zero inflation</a> </p> <a href="https://publications.waset.org/abstracts/70280/tests-for-zero-inflation-in-count-data-with-measurement-error-in-covariates" class="btn btn-primary btn-sm">Procedia</a> <a href="https://publications.waset.org/abstracts/70280.pdf" target="_blank" class="btn btn-primary btn-sm">PDF</a> <span class="bg-info text-light px-1 py-1 float-right rounded"> Downloads <span class="badge badge-light">288</span> </span> </div> </div> <div class="card paper-listing mb-3 mt-3"> <h5 class="card-header" style="font-size:.9rem"><span class="badge badge-info">122</span> Legislator’s Liability – Sovereign Immunity and Rule of Law</h5> <div class="card-body"> <p class="card-text"><strong>Authors:</strong> <a href="https://publications.waset.org/abstracts/search?q=Isabel%20Mousinho%20de%20Figueiredo">Isabel Mousinho de Figueiredo</a> </p> <p class="card-text"><strong>Abstract:</strong></p> Traditionally it was held that the king can do no wrong. History has proved otherwise, and both the rule of law and the open society call for a diversification of checks and balances, including civil liability in tort. Most jurisdictions are right to fear the excessive cost of such liability for the innocent taxpayer. There are notwithstanding extreme instances where refusing compensation is perceived to be outrageous. Many public bodies end up handing out on a voluntary basis, which leaves room to question its legality and merit. Instead, some criteria can shed light on the fairness of an underlying rationale of such compensation and cordon it off within reasonable limits. <p class="card-text"><strong>Keywords:</strong> <a href="https://publications.waset.org/abstracts/search?q=comparative%20law" title="comparative law">comparative law</a>, <a href="https://publications.waset.org/abstracts/search?q=liability%20of%20legislators" title=" liability of legislators"> liability of legislators</a>, <a href="https://publications.waset.org/abstracts/search?q=public%20bodies" title=" public bodies"> public bodies</a>, <a href="https://publications.waset.org/abstracts/search?q=tort%20law" title=" tort law"> tort law</a> </p> <a href="https://publications.waset.org/abstracts/155066/legislators-liability-sovereign-immunity-and-rule-of-law" class="btn btn-primary btn-sm">Procedia</a> <a href="https://publications.waset.org/abstracts/155066.pdf" target="_blank" class="btn btn-primary btn-sm">PDF</a> <span class="bg-info text-light px-1 py-1 float-right rounded"> Downloads <span class="badge badge-light">111</span> </span> </div> </div> <div class="card paper-listing mb-3 mt-3"> <h5 class="card-header" style="font-size:.9rem"><span class="badge badge-info">121</span> Thermodynamic Attainable Region for Direct Synthesis of Dimethyl Ether from Synthesis Gas</h5> <div class="card-body"> <p class="card-text"><strong>Authors:</strong> <a href="https://publications.waset.org/abstracts/search?q=Thulane%20Paepae">Thulane Paepae</a>, <a href="https://publications.waset.org/abstracts/search?q=Tumisang%20Seodigeng"> Tumisang Seodigeng</a> </p> <p class="card-text"><strong>Abstract:</strong></p> This paper demonstrates the use of a method of synthesizing process flowsheets using a graphical tool called the GH-plot and in particular, to look at how it can be used to compare the reactions of a combined simultaneous process with regard to their thermodynamics. The technique uses fundamental thermodynamic principles to allow the mass, energy and work balances locate the attainable region for chemical processes in a reactor. This provides guidance on what design decisions would be best suited to developing new processes that are more effective and make lower demands on raw material and energy usage. <p class="card-text"><strong>Keywords:</strong> <a href="https://publications.waset.org/abstracts/search?q=attainable%20regions" title="attainable regions">attainable regions</a>, <a href="https://publications.waset.org/abstracts/search?q=dimethyl%20ether" title=" dimethyl ether"> dimethyl ether</a>, <a href="https://publications.waset.org/abstracts/search?q=optimal%20reaction%20network" title=" optimal reaction network"> optimal reaction network</a>, <a href="https://publications.waset.org/abstracts/search?q=GH%20Space" title=" GH Space"> GH Space</a> </p> <a href="https://publications.waset.org/abstracts/48978/thermodynamic-attainable-region-for-direct-synthesis-of-dimethyl-ether-from-synthesis-gas" class="btn btn-primary btn-sm">Procedia</a> <a href="https://publications.waset.org/abstracts/48978.pdf" target="_blank" class="btn btn-primary btn-sm">PDF</a> <span class="bg-info text-light px-1 py-1 float-right rounded"> Downloads <span class="badge badge-light">240</span> </span> </div> </div> <div class="card paper-listing mb-3 mt-3"> <h5 class="card-header" style="font-size:.9rem"><span class="badge badge-info">120</span> A Survey on Quasi-Likelihood Estimation Approaches for Longitudinal Set-ups</h5> <div class="card-body"> <p class="card-text"><strong>Authors:</strong> <a href="https://publications.waset.org/abstracts/search?q=Naushad%20Mamode%20Khan">Naushad Mamode Khan</a> </p> <p class="card-text"><strong>Abstract:</strong></p> The Com-Poisson (CMP) model is one of the most popular discrete generalized linear models (GLMS) that handles both equi-, over- and under-dispersed data. In longitudinal context, an integer-valued autoregressive (INAR(1)) process that incorporates covariate specification has been developed to model longitudinal CMP counts. However, the joint likelihood CMP function is difficult to specify and thus restricts the likelihood based estimating methodology. The joint generalized quasilikelihood approach (GQL-I) was instead considered but is rather computationally intensive and may not even estimate the regression effects due to a complex and frequently ill conditioned covariance structure. This paper proposes a new GQL approach for estimating the regression parameters (GQLIII) that are based on a single score vector representation. The performance of GQL-III is compared with GQL-I and separate marginal GQLs (GQL-II) through some simulation experiments and is proved to yield equally efficient estimates as GQL-I and is far more computationally stable. <p class="card-text"><strong>Keywords:</strong> <a href="https://publications.waset.org/abstracts/search?q=longitudinal" title="longitudinal">longitudinal</a>, <a href="https://publications.waset.org/abstracts/search?q=com-Poisson" title=" com-Poisson"> com-Poisson</a>, <a href="https://publications.waset.org/abstracts/search?q=ill-conditioned" title=" ill-conditioned"> ill-conditioned</a>, <a href="https://publications.waset.org/abstracts/search?q=INAR%281%29" title=" INAR(1)"> INAR(1)</a>, <a href="https://publications.waset.org/abstracts/search?q=GLMS" title=" GLMS"> GLMS</a>, <a href="https://publications.waset.org/abstracts/search?q=GQL" title=" GQL"> GQL</a> </p> <a href="https://publications.waset.org/abstracts/40051/a-survey-on-quasi-likelihood-estimation-approaches-for-longitudinal-set-ups" class="btn btn-primary btn-sm">Procedia</a> <a href="https://publications.waset.org/abstracts/40051.pdf" target="_blank" class="btn btn-primary btn-sm">PDF</a> <span class="bg-info text-light px-1 py-1 float-right rounded"> Downloads <span class="badge badge-light">354</span> </span> </div> </div> <div class="card paper-listing mb-3 mt-3"> <h5 class="card-header" style="font-size:.9rem"><span class="badge badge-info">119</span> A Comparison of Methods for Estimating Dichotomous Treatment Effects: A Simulation Study</h5> <div class="card-body"> <p class="card-text"><strong>Authors:</strong> <a href="https://publications.waset.org/abstracts/search?q=Jacqueline%20Y.%20Thompson">Jacqueline Y. Thompson</a>, <a href="https://publications.waset.org/abstracts/search?q=Sam%20Watson"> Sam Watson</a>, <a href="https://publications.waset.org/abstracts/search?q=Lee%20Middleton"> Lee Middleton</a>, <a href="https://publications.waset.org/abstracts/search?q=Karla%20Hemming"> Karla Hemming</a> </p> <p class="card-text"><strong>Abstract:</strong></p> Introduction: The odds ratio (estimated via logistic regression) is a well-established and common approach for estimating covariate-adjusted binary treatment effects when comparing a treatment and control group with dichotomous outcomes. Its popularity is primarily because of its stability and robustness to model misspecification. However, the situation is different for the relative risk and risk difference, which are arguably easier to interpret and better suited to specific designs such as non-inferiority studies. So far, there is no equivalent, widely acceptable approach to estimate an adjusted relative risk and risk difference when conducting clinical trials. This is partly due to the lack of a comprehensive evaluation of available candidate methods. Methods/Approach: A simulation study is designed to evaluate the performance of relevant candidate methods to estimate relative risks to represent conditional and marginal estimation approaches. We consider the log-binomial, generalised linear models (GLM) with iteratively weighted least-squares (IWLS) and model-based standard errors (SE); log-binomial GLM with convex optimisation and model-based SEs; log-binomial GLM with convex optimisation and permutation tests; modified-Poisson GLM IWLS and robust SEs; log-binomial generalised estimation equations (GEE) and robust SEs; marginal standardisation and delta method SEs; and marginal standardisation and permutation test SEs. Independent and identically distributed datasets are simulated from a randomised controlled trial to evaluate these candidate methods. Simulations are replicated 10000 times for each scenario across all possible combinations of sample sizes (200, 1000, and 5000), outcomes (10%, 50%, and 80%), and covariates (ranging from -0.05 to 0.7) representing weak, moderate or strong relationships. Treatment effects (ranging from 0, -0.5, 1; on the log-scale) will consider null (H0) and alternative (H1) hypotheses to evaluate coverage and power in realistic scenarios. Performance measures (bias, mean square error (MSE), relative efficiency, and convergence rates) are evaluated across scenarios covering a range of sample sizes, event rates, covariate prognostic strength, and model misspecifications. Potential Results, Relevance & Impact: There are several methods for estimating unadjusted and adjusted relative risks. However, it is unclear which method(s) is the most efficient, preserves type-I error rate, is robust to model misspecification, or is the most powerful when adjusting for non-prognostic and prognostic covariates. GEE estimations may be biased when the outcome distributions are not from marginal binary data. Also, it seems that marginal standardisation and convex optimisation may perform better than GLM IWLS log-binomial. <p class="card-text"><strong>Keywords:</strong> <a href="https://publications.waset.org/abstracts/search?q=binary%20outcomes" title="binary outcomes">binary outcomes</a>, <a href="https://publications.waset.org/abstracts/search?q=statistical%20methods" title=" statistical methods"> statistical methods</a>, <a href="https://publications.waset.org/abstracts/search?q=clinical%20trials" title=" clinical trials"> clinical trials</a>, <a href="https://publications.waset.org/abstracts/search?q=simulation%20study" title=" simulation study"> simulation study</a> </p> <a href="https://publications.waset.org/abstracts/154314/a-comparison-of-methods-for-estimating-dichotomous-treatment-effects-a-simulation-study" class="btn btn-primary btn-sm">Procedia</a> <a href="https://publications.waset.org/abstracts/154314.pdf" target="_blank" class="btn btn-primary btn-sm">PDF</a> <span class="bg-info text-light px-1 py-1 float-right rounded"> Downloads <span class="badge badge-light">114</span> </span> </div> </div> <ul class="pagination"> <li class="page-item disabled"><span class="page-link">&lsaquo;</span></li> <li class="page-item active"><span class="page-link">1</span></li> <li class="page-item"><a class="page-link" href="https://publications.waset.org/abstracts/search?q=covariate%20balances&page=2">2</a></li> <li class="page-item"><a class="page-link" href="https://publications.waset.org/abstracts/search?q=covariate%20balances&page=3">3</a></li> <li class="page-item"><a class="page-link" href="https://publications.waset.org/abstracts/search?q=covariate%20balances&page=4">4</a></li> <li class="page-item"><a class="page-link" href="https://publications.waset.org/abstracts/search?q=covariate%20balances&page=5">5</a></li> <li class="page-item"><a class="page-link" href="https://publications.waset.org/abstracts/search?q=covariate%20balances&page=2" 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