Activity-Accessibility Models of Trip Generation : Progress Report

This research examined the trip generation process with the specific purpose of evaluating the effect of activity-accessibility variables on trip generation.Another aspect of accessibility was studied by stratifying the zones of the study area by location.In contrast to XV 1985 forecasts of the demographic, socio-economic, and land use variables together with estimates of travel time on the proposed future network were inputs to the four sets of developed models to forecast trip productions and attractions.Comparison of these forecasts indicated that stratified models forecasted, on the average, more trips for zones of the non central area and less for zones of the central area compared to forecasts made by unstratified models.Forecasts by models with accessibility variables and stratification were significantly different, on the average, than forecasts by basic IRTADS models.There were some trip purposes for which IRTADS models indicated, on the average, larger trip forecasts than the accessibility models with stratification.Further analysis on those trip purposes showed that the zones where the IRTADS models did not overforecast trips were in the vicinity and along cor- ridors defined by the major thoroughfares of the study areaThe results of this research recommend that future relative accessibility of zones of the study area be considered in estimating future trips.The process would be iterative and would be terminated when equilibrium is reached between the forecasted demand for transportation (future trips) and planned for supply of transportation ( future network ) .CHAPTER I.