Travel Demand Model - OKI

OKI/MVRPC Travel Demand Model – Version 6.04. Trip ProductionsTrip productions for four trip purposes are estimated in Step15, the third step in the TripGeneration program: home-based work, home-based university, home-based school and homebasedother. Trip productions were initially estimated by applying the OKI trip production rates,and were later adjusted in the process of validating to the MVRPC original estimates and to thehighway observed VMT.4.1 Model AdjustmentsWhen applying the OKI trip production rates to the entire region, it was observed that thisunderestimates work trips in Montgomery, Greene and Miami counties by approximately 25%,when compared with MVRPC's Base 94 model estimates. On average, the OKI model estimates1.2 HBW trip productions per worker, while the MVRPC model estimates 1.6 HBW tripproductions per worker. The difference may be due to higher trip linking rates in the Cincinnatiregion, due to their higher trip lengths and possibly to increased trip linking opportunities. At thesame time, the OKI model underestimates HBO trip productions in the MVRPC region.Given that both OKI and MVRPC trip rates are reasonable and were originally estimated fromlocal survey data, the consolidated model applies OKI home-based work and home-based othertrip rates to the OKI zones (1-1608) and MVRPC home-based work and home-based other ratesto the MVRPC zones (1609-2425). The scale factors were initially set to the values in theiroriginal models, and were later adjusted in the process of validating the highway network VMTestimates. Please see Section 6.0 for a more detailed analysis of the trip production estimates.The trip production rates and scale factors used in version 6.0 are shown in Appendix B.The consolidated model uses the same trip production rates as model version 5.4 for the othertwo home-based purposes: university and school. Please refer to the Methodology andValidation Report cited above for a full description of these models. The trip production rates areshown in Appendix 2.In Step 15 trip productions are grouped by market segment, for use later in mode choice. Themarket segmentation used in model version 5.4 was changed so that the new marketsegmentation is consistent with the updated mode choice model. So, in version 6.0 of theOKI/MVRPC model, the following market segments apply:• For HBW, the trip markets are defined by auto ownership and number of workers perhousehold, as follows:o Zero auto householdso Households with less cars than workerso Households with equal numbers of cars and workerso Households with more cars than workers• For HBO, the trip markets are defined by auto ownership, as follows:o Zero auto householdso One auto householdso Two auto householdso Households with three or more autos• For HBU and NHB, no market segmentation is applied.Trip Generation - Trip Productions 12