Two-component Poisson mixture regression is typically used to model heterogeneous count outcomes that arise from two underlying sub-populations. Furthermore, a random component can be incorporated into the linear predictor to account for the clustering data structure. However, when including random effects in both components of the mixture model, the two random effects are often assumed to be i...

The term prediction implies expected outcome in the future, often based on a model and statistical inference. Longitudinal imaging studies offer the possibility to model temporal change trajectories of anatomy across populations of subjects. In the spirit of subject-specific analysis, such normative models can then be used to compare data from new subjects to the norm and to study progression o...

Motivation: Mixed linear models provide important techniques for performing genome-wide association studies. However, current models have pitfalls associated with their strong assumptions. Here, we propose a new implementation designed to overcome some of these pitfalls using an empirical Bayes algorithm. Results: Here we introduce NAM, an R package that allows user to take into account prior i...

BACKGROUND Local migration in developing-world settings, particularly among rural populations, is an important yet understudied demographic process. Research on migration in such populations can help us test and inform anthropological and demographic theory. Furthermore, it can lead to a better understanding of modern population distributions and epidemiologic landscapes. OBJECTIVE The purpose ...

Some investigations associated with large government surveys typically require statistical analysis for populations that have a complex hierarchical structure. Classical analysis often fail to account for the nature of complex sampling designs and possibly result in incorrect inference for the parameters of interest. Linear mixed models can be used to analyze survey data collected from such pop...

Survey sampling often supplies information about a study variable only for sampled elements. However, auxiliary information is often available for the entire population. The relationship of the auxiliary information with the study variable across the sample allows inferences about the nonsampled portion of the population. Thus, auxiliary information can be used to improve upon survey estimation...

Problem: It is often assumed that the heritability of performance traits (function) can be estimated by the heritability of primary traits (e.g. form). It is also frequently assumed that performance traits should be less heritable than primary traits. These assumptions should be carefully evaluated rather than assumed. One common area of study in which these assumptions have been made is anti-p...

In general the importance of functional traits is increasing in all dairy cattle populations over the last decade. Beside udder and fertility problems claw and foot disorders are main involuntary culling reasons. Linear description of feet and leg traits in the frame of conformation scoring didn’t reduce claw and leg problems as expected. Therefore new ways of data recording should be establish...

Low college enrollment rates among low income students may stem from credit constraints, low academic skill, low quality schools, or some combination of these. RecentMassachusetts data allow the first use of school district fixed effects in the analysis of credit constraints, leading to four primary findings. First, Massachusetts’ low income students have lower intended college enrollment rates...