Preparatory work based on the 1947 origin and destination study data and on some of the 1960 data indicates the relationships that would be helpful in making a complete modal split model for the Penn jersey region. The basic approach can be considered as focusing on two items' /1/ that mass transit trips could properly be divided into the five distinctly different trip purposes but need not be divided into trips by type of land use as the origin, and /2/ that the predictive model should include components which express the rider, the density of development and the transportation system. The following types of trips and relationships were selected in simulating and projecting the transit trips in the Penn jersey region' home to work trips, home to non-work trips, work to home trips, non-work to home trips, and non-home to non-home trips. Several conclusions of relevance to this study are' /1/ the selection of five transit trip types to be analysed, simulated, and projected produced satisfactory and reasonably reliable results, /2/ the modal split model incorporates simultaneously one variable descriptive of the rider, another variable descriptive of the area of trip origination, and two variables directly descriptive of the systems serving the area and the region, /3/ three system variables were selected for this modal split model' implied density /or proximity/ of transit lines in a measure of residential or job density in a district, system accessibility combining three different features of the highway and transit system in addition to two area features, and the frequency of transit service which is descriptive of the availability of transit service in a district, /4/ each of the five trip purposes indicates a particular dependence on only one or two of the five variables incorporated in the model, and /5/ the verified relationships between transit trips and car ownership, density of development, system variables, and sensitivity and range of applicability of this model open new possibilities for transportation systems planning in an urban area.
Abstract