Statistical Models of At-grade Intersection Accidents

DTFH61-92-C-00031The objective of this research was to develop statistical models of the relationship between traffic accidents and highway geometric elements for at-grade intersections. These models also incorporated the effect of traffic control features and traffic volumes on intersection accidents. The data base used to develop the models was obtained from the California Department of Transportation. Field data were also collected for a sample of urban, four-leg, signalized intersections to provide data on additional geometric design variables and turning-movement counts that were not available from existing highway agency files. The statistical modeling approaches used in the research included Poisson, lognormal, negative binomial, and logistic regression, as well as discriminant and cluster analysis. Regression models of the relationships between accidents and intersection geometric design, traffic control, and traffic volume variables were found to explain between 16 and 38% of the variability in the accident data. However, most of that variability was explained by the traffic volume variables considered; geometric design variables accounted for only a very small additional portion of the variability. An evaluation of hard-copy police accident reports by three independent reviewers for a sample of eight urban, four-leg, signalized intersections found that only 5 to 14% of the accidents had causes that appeared to be related to geometric design features of the intersections

The thermal performance of earth covered buildings in hot, arid regions /

"Work Performed Under Contract No. EG-77-C-01-4042.""October 1980."Includes bibliographical references.Mode of access: Internet

Base line forecasts of resource recovery, 1972 to 1990 : final report /

Photoreprint edition.Bibliography: p. 367-376.Mode of access: Internet

Zn₃P₂ as an improved semiconductor for photovoltaic solar cells : ninth quarterly report for September 1 - November 31, 1980 /

"Work Performed Under Contract No. AC02-77CH00178.""Subcontract no.Mode of access: Internet

Indium phosphide/cadmium sulfide thin-film solar cells : quarterly report for period July - October 1980 /

"Work Performed Under Contract No. AC02-77CH00178.""Contract XZ-0-9196-1.""January 1981."Mode of access: Internet

Thin film polycrystalline silicon solar cells : first technical progress report for April 15 - July 15, 1980.

"Work Performed Under Contract No. AC02-77CH00178.""July 1980."Includes bibliographical references (page 22).Mode of access: Internet

International passive architectural survey ; announcement of results /

"Prepared Under Task No. 6324.40.""Work Performed Under Contract No. EG-77-C-01-4042.""October 1980."Includes bibliographical references.Mode of access: Internet

Photovoltaic research branch semiannual report : period covered : 1 October 1979 to 31 March 1980 /

This report covers SERI research activities on solid-state theory, high-efficiency cells, thin-film cells, silicon purification, silicon crystallization, thick-film technology, surface and interface analysis, and growth of GaAs and related compounds by metal-organic chemical vapor desposition."SERI/PR-611-737."Includes bibliographical references (pages PS-9 to PS-11.This report covers SERI research activities on solid-state theory, high-efficiency cells, thin-film cells, silicon purification, silicon crystallization, thick-film technology, surface and interface analysis, and growth of GaAs and related compounds by metal-organic chemical vapor desposition.Contract no."Prepared under Task no. 3221.10."Mode of access: Internet

Workshop on Development of the Interactive Highway Safety Design Model Accident Analysis Module

DTFH61-93-Z-00173The Federal Highway Administration is developing an Interactive Highway Safety Design Model (IHSDM) to assist highway geometric design engineers in considering the safety consequences of their design decisions. One element of the IHSDM will be an accident analysis module. A workshop was held in June 1995 to evaluate two approaches to developing the accident analysis module: the statistical approach and the diagnostic approach. The workshop recommended that the accident analysis module include statistical models that provide both point and interval estimates of safety measures. Statistical techniques for model development could include linear regression; generalized linear models; Classification and Regression Tree (CART) analysis; Bayesian approximation; multivariate analysis; jackknifing, bootstrapping, and subsampling techniques; and nonparametric methods. It was recommended that formal statistical models be combined with an expert systems approach to identify potential safety problems associated with geometric design features. The workshop also recommended that a diagnostic approach to the development of the accident analysis module be pursued. The diagnostic approach would employ a combination of accident reconstruction from hard-copy police accident reports and on-scene accident investigation. A key element of the diagnostic approach would be identifying the sequence of events leading to particular accidents and the causal or contributing role of specific geometric features in that sequence of events. This report presents the workshop recommendations for both the statistical and diagnostic approaches to accident analysis

Electrochemical photovoltaic cells : quarterly technical progress report for April 15 - July 31, 1980 /

"Work Performed Under Contract No. AC02-77CH00178.""September 1980."Mode of access: Internet