Forecasting highway casualties: The British road safety act and a sense of déja vu

This paper reexamines the effect of the introduction of the British Road Safety Act of 1967. We construct a dynamic model relating monthly road casualties to road traffic, rainfall, and alcohol consumption, standardizing for the seasonality in the data. An intervention variable captures the effect of the Road Safety Act. The findings confirm Ross's earlier conclusion that the Road Safety Act significantly reduces casualties. However, we find that the Road Safety Act only accounts for 2.7 percent of the variance in road casualties, while miles-driven and rainfall account for 48.8 percent, and alcohol consumption explains 4.2 percent. Our model forecasts accurately for 24 months beyond December, 1972, the last month used for estimation.     

The influence of police interventions and alternative income sources on the dynamic process of choosing crime as a career

This paper demonstrates how a rational process of choice may be influenced by both deterrence forces and economic opportunities. This choice is modeled by a dynamic (Markov) process which captures self-sorting by youth among the categories of innocents, desisters, and persisters. in crime. A key to the results is the introduction of the perceived probability of punishment and its influence on the sorting process. The analysis shows how this force and the availability, or lack of, economic opportunities or income sources modify transition probabilities. The long-run consequences will be a larger subpopulation of individuals who have experimented with crime but subsequently revert to crime-free behavior and a smaller subpopulation of individuals who commit a greater share of crime. Empirical evidence is based on data from the New Youth Cohort of the National Longitudinal Surveys.     

PTSD Symptoms Experienced and Coping Tactics Used by Crime Scene Investigators in the United States

Few investigations have assessed the prevalence of posttraumatic stress experiences among Crime Scene Investigators (CSIs). We recruited a nationwide sample of 225 CSIs to complete online questionnaires assessing PTSD symptoms, use of specific coping tactics, perceived social support, trait resilience, and demographics. Seven symptoms had been experienced by at least 50% of participants during the previous month, and 9.3% had total checklist scores suggestive of PTSD. A significant regression analysis revealed that higher PTSD scores were associated with drinking alcohol more frequently to deal with stress, admitting more frequently one could not deal with stress and not trying to do so, lower social support, getting angry and letting emotions out more frequently, lower resilience, and finding comfort in one's religious beliefs. Given the proportions of CSIs that experience exposure‐related stress, more should be done to mitigate the prevalence and severity of these symptoms.