Press Releases

ASI Employee to Speak on Linear Mixed Models at APHA Conference

A senior research statistician in ASI's Statistics and Public Health Research (SPHR) Division, Orelien uses LMM to analyze data from longitudinal studies. His presentation, "Assessing Model Adequacy in the Linear Mixed Model," is based on his research to identify tools that enable researchers to determine whether an LMM that has been applied to a longitudinal data is a good fit or if another model is needed.

His research offers participants an overview of the tools available for assessing model adequacy in LMM. Orelien also plans to discuss the limitations of current methods in assessing model adequacy, to present a more intuitive statistic for assessing goodness of fit in LMMs and to demonstrate how well the new statistic performs based on simulation results.

At ASI, Orelien manages the statistical functions for several clients, including the National Institute for Occupational Safety and Health (NIOSH)'s "Needlestick" project, a study to determine the factors affecting exposure to blood among non-hospital-based health-care workers.

Orelien also consults with clients, designs and oversees the implementation of statistical analysis plans, and writes project reports and technical information for project proposals. He holds a bachelor's in mathematics from Rutgers University and a master's in statistics from North Carolina State University. Orelien is completing a doctorate in biostatistics at the University of North Carolina at Chapel Hill.

About ASI

ASI is a professional services company dedicated to enhancing human health through innovative science, technology and knowledge solutions. Founded in 1983, ASI conducts research and provides technical and professional services to help government and industry clients identify and solve problems affecting human health. ASI scientists and specialists offer expertise in public health research, research administration and science management, health communications, information technology, scientific data management, biostatistics and clinical research. ASI serves clients in healthcare and public health, biodefense, science management and research, and civil government markets.