"During the first year of work conducted by the Council for Advanced Transportation Studies (CATS) on Topic II, "The Environmental Impact of Interurban Transportation Systems on Rural Communities," it became apparent that large quantities of data would be collected. Part of the research required measuring and evaluating the transportation impact on an entire community, Sealy, Texas, for a 20-year period, from 1950 to 1970. The major task was to create descriptive models of changes during that period within the community and the transportation system, a task which has involved collecting and managing an extensive data base. Specifically, two large data sets were compiled. The first contained economic data, the second, an inventory of land sales compiled from title policies written for individual sales. This latter set contains over 20,000 pieces of data, including information covering 600 sales of parcels.with 35 variables for each. The first problems encountered entailed the storing and updating of these large data sets and the manipulation of the completed data sets at a reasonable cost in manpower and computer time. The information had to be accessible for multiple regression analysis and various other statistical analyses. A system was needed that was simple enough that persons with little experience could use the system and acquire results with a minimum outlay of effort. Thus the system had to be convenient and yet remain flexible enough to meet the requirements of different kinds of data."--Introduction