Institute of Transportation, MOTC

       Population, population density and regional development level are the factors contributing to crash frequency and severity. In this paper, regression analysis, multi-level regression and growth model analysis were developed to model the crash data from 19 cities in Taiwan over 4 years. The relationship between regional development and traffic crashes were evaluated. The results indicate that population, population density, immigrant population, road area, population concentration are significant factors to crash frequency. Population, population density, road area, and population concentration are positively related to crash frequency. Immigrant population is negatively related to crash frequency. The results for fatal traffic accident reveal that Population, the proportion of males, the number of violations per trip, the proportion of young people, hospital concentration and the number of ambulance are significant. Population, the proportion of males, the number of violations per trip, the proportion of young people, and the hospital concentration are positively related to fatal traffic accident. The number of ambulance is negatively related to fatal traffic accident. The estimation results of multi-level regression analysis show that when population, population density, immigrant population, road area and population concentration are under control, the number of traffic accidents in New Taipei City are fewer than other cities in Taiwan. The number of traffic accidents in Taipei and Hsinchu are higher than other cities in Taiwan. In addition, the population change in Tainan has less impact on traffic accidents than other cities. The population change in Kaohsiung City and Hualien County has greater impact on traffic accidents than in other cities. The estimation result of multi-level regression for the number of fatal traffic accidents show that when population, population density, the number of hospitals, the proportion of young people, the concentration of ambulances, the population concentration, and the immigrant population are under control, the number of fatal traffic accidents in Pingtung County are fewer than other cities. The numbers of fatal traffic accidents in Taoyuan are more than other cities. Besides, the population change in Tainan has less impact on the fatal traffic accidents than other cities. The population change in Pingtung has greater impact on the fatal traffic accidents than in other cities. The results of growth model suggest that the annual change of traffic accidents in urban areas in Taiwan has increased year after year, and the annual change of fatal traffic accidents has decreased year after year.