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Software to Assist TDM Programs

Trip Reduction Impacts for Mobility Management Strategies (TRIMMS)

One of the objectives of the Economics of TDM: Comparative Cost Effectiveness and Public Investment study was to develop a methodology that combines academic and practitioner experiences within a theoretical framework that truly captures consumers' price responsiveness to diverse transportaiton options by embracing the most relevant trade-offs faced under income, modal price and availability constraints. The development of the theoretical model leads to the design and implementation of TRIMMS (Trip Reduction Impacts for Mobility Management Strategies), a practitioner-oriented sketch planning tool. TRIMMS permits program managers and funding agencies like FDOT to make informed decisions on where to spend finite transportation dollars based on a full range of benefits and costs. The approach is consistent with other benefit to cost analyses. Its accuracy and the perceived fairness are critical when significant funds are at stake. The model allows some regions to use local data or opt to use defaults from national research findings, select the benefits and costs of interest, and calculate the costs and benefits of a given program. A step-by-step introduction to the program, its capabilities, and a set of working examples to guide the user through the process of evaluation is included in the report. A key strength of this model is its wide range of benefits and costs that can be selected for the analysis. The model's flexibility and robustness allows it to be adopted by agencies throughout the country. A byproduct of this research effort that goes beyond the initial project objectives is the development of a structured approach to evaluate the impact of soft programs. Compared to the currently available soft program evaluations methods, the approach developed in the report provides a less heuristic method of estimation resulting in statistically robust mode share impact predictions. For more information, contact Sisinnio Concas at concas@cutr.usf.edu. 

Download model - TRIMMS_1.0.xls or Download model (zip file)

Worksite Trip Reduction Model and Manual

This model predicts changes in vehicle trip rate (think # vehicles per 100 employees) and is available online http://www.nctr.usf.edu/worksite/ or as look-up tables in the final report (see Chapter 5 in http://www.nctr.usf.edu/pdf/473-14.pdf )

According to Institute of Transportation Engineers, assessing the trip reduction claims from transportation demand management (TDM) programs is an issue for estimating future traffic volumes from trip generation data. To help assess those claims, a Worksite Trip Reduction Model and Manual was produced using existing data on programs, services and incentives contained in thousands of before and after worksite trip reduction plans. Models were built using linear regression and non-linear neural networks with the change in vehicle trip rate (VTR) as the dependent variable. The neural network model built on equally sampled data was the best generalized model based on three performance measures: the accuracy across the moderate range of change in VTR; the accuracy on full range of change in VTR and the R-square between the actual change in VTR and the predicted change in VTR. Worksite trip reduction plans explain a modest portion of the change in vehicle trip rates from one year to the next.  The aggregate nature of the data loses the ability to explain whether the change in mode behavior was influenced by the programs or changes in the workforce or other exogenous variables.  http://www.nctr.usf.edu/pdf/473-14.pdf

EPA COMMUTER Model

This model calculates the transportation and emissions benefits of Commuter Choice and other voluntary strategies to reduce solo commuting. It is designed to be usable by people with basic computer skills who do not necessarily have experience with models. COMMUTER offers two levels of analysis: Regional analyses can be done on programs covering an urban area, a central business district or a highly-traveled corridor. Site- specific analyses enable benefits to be projected for programs at individual worksites. 

Business Benefits Calculator

The U.S. Environmental Protection Agency (EPA) developed a Web-based Calculator at http://www.bestworkplaces.org/resource/calc.htm that enables an employer considering Best Workplaces for CommutersSM to estimate the financial, environmental, traffic-related, and other benefits of joining the program. This tool was developed in two formats: Fully Interactive and Text-Only (accessible to those using assistive technology) .

Ridematching Systems


A list of Ridematching Systems with a variety of features and delivery methods.  Nothing should be construed as an endorsement of any or all these products.  

 

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