The method of generalized estimating equations (GEE) is a popular tool for analysing longitudinal (panel) data. Often, the covariates collected are time-dependent in nature, for example, age, relapse status, monthly income. When using GEE to analyse longitudinal data with time-dependent covariates, crucial assumptions about the covariates are necessary for valid inferences to be drawn. When tho...

The interpretation and diagnostic value of the ophthalmic artery pressure measurement and ocular pulse timing modes of the 500 mm Hg vacuum OPG-Gee ocular pneumoplethysmograph were evaluated in 65 patients who underwent aortic arch and cerebral arteriography. Data analysis revealed the OPG-Gee differential tracing which electronically compares and amplifies differences between the right and lef...

Generalized estimating equations (GEE) are commonly employed for the analysis of correlated data. However, the quadratic inference function (QIF) method is increasing in popularity because of its multiple theoretical advantages over GEE. We base our focus on the fact that the QIF method is more efficient than GEE when the working covariance structure for the data is misspecified. It has been sh...

Many applied problems arising in agricultural monitoring and food security require reliable crop maps at national or global scale. Large scale crop mapping requires processing and management of large amount of heterogeneous satellite imagery acquired by various sensors that consequently leads to a “Big Data” problem. The main objective of this study is to explore efficiency of using the Google ...

The estimation of correlation parameters has received attention for both its own interest and improvement of the estimation efficiency of mean parameters by the generalized estimating equations (GEE) approach. Many of the well-established methods for the estimation of correlation parameters can be constructed under the GEE framework which is, however, sensitive to outliers. In this paper, we co...

1 In this paper, the necessity for treating intra-household correlation is investigated by analyzing 2 two travel behavior indices, i.e. travel time and travel distance, for three important travel motives 3 (commuting, shopping, and leisure). Data stemming from the 2010 Belgian National Household 4 Travel Survey are used in the analysis. Two model approaches that accommodate for intra5 househol...

GENERALIZED ESTIMATING EQUATION BASED ZERO-INFLATED MODEL WITH APPLICATION TO EXAMINING THE RELATIONSHIP BETWEEN DENTAL CARIES AND FLUORIDE EXPOSURES Sheng Xu April 16, 2013 In the study of dental caries, the number of caries is frequently characterized by over-dispersion and excessive zeros. In addition, the numbers of caries from the same subject are correlated. Zero-Inflated (ZI) regression ...

It is common in longitudinal studies for scheduled visits to be accompanied by as-needed visits due to medical events occurring between scheduled visits. If the timing of these as-needed visits is related to factors that are associated with the outcome but are not among the regression model covariates, naively including these as-needed visits in the model yields biased estimates. In this paper,...