Trip Generation of Selected Industrial Groups.

This paper determines the factors influencing commercial vehicle trip generation for selected industrial groups, and quantifies their effects using multiple regression analysis. Two methods of selecting the groups were adopted: one using eight of the Standard Industrial Classes; and one which attempted to put industries having similar vehicle generation characteristics into the same group, by subdividing SIC groups or by grouping together industries with similar manufacturing or trading processes. The survey combined an initial interview of firm's management about the operations of the firm with a recording by the firm of their travel data, using a sample of firms in the West Yorkshire metropolitan area. Of 22 relationships developed, 15 were considered acceptable descriptors of the variations in trip making, but only in 3 cases did a single variable (such as total floor area or total employees) account for more than 70 percent of the variation, and no single variable type gave the best fit for the various groups investigated.