Modeling Heterogeneity:

This book addresses the impact of critical modeling
issues on the statistical significance of
specifications correlated with traffic accident
frequencies. Also, this book intends to shed new
light on the major factors contributing to the
occurrence of median crossover accidents.
Furthermore, the research aims to lay out
methodologies that provide significant
improvements in frequency predictions. In traffic
accident databases that are comprised of cross-
sectional panels, unobserved effects or
heterogeneity, correlation due to shared unobserved
effects through accident counts, and excess zero
problems are common issues in the estimation of
accident count models. Various modeling structures
are considered with application to median crossover
accident frequencies -- this is the main
contribution of the book. The median crossover
accident problem helps illustrate the viability of
alternative methods for heterogeneity treatment in
traffic accident contexts.

Autorentext

Dr. Sittikariya is a senior transportation engineer and project manager at DKS Associates in Seattle. Dr. Shankar is an Associate Professor of Civil and Environmental Engineering at the Pennsylvania State University. Mr. Venkataraman is a transportation engineering consultant with expertise in managing database related to traffic safety.

Klappentext

This book addresses the impact of critical modeling issues on the statistical significance of specifications correlated with traffic accident frequencies. Also, this book intends to shed new light on the major factors contributing to the occurrence of median crossover accidents. Furthermore, the research aims to lay out methodologies that provide significant improvements in frequency predictions. In traffic accident databases that are comprised of cross-sectional panels, unobserved effects or heterogeneity, correlation due to shared unobserved effects through accident counts, and excess zero problems are common issues in the estimation of accident count models. Various modeling structures are considered with application to median crossover accident frequencies -- this is the main contribution of the book. The median crossover accident problem helps illustrate the viability of alternative methods for heterogeneity treatment in traffic accident contexts.