Institute of Transportation Studies at UC Berkeley

We have reviewed the key components of the California High Speed Rail Ridership Studies. The primary contractor for these studies, Cambridge Systematics (CS), has followed generally accepted professional standards in carrying out the demand modeling and analysis. Nevertheless we have found some significant problems that render the key demand forecasting models unreliable for policy analysis. This Executive Summary describes the most serious problems. The body of this report elaborates on these problems and describes additional concerns we have. In broad terms, the approach taken by CS includes a model development phase and a model validation phase. In the model development phase, both historical data and survey data were employed to develop a mathematical model of interregional travel. The individuals surveyed were interregional trip makers. However, the mode choices of the individuals surveyed were not representative of California interregional travelers. For example, nearly 90% of long distance (over 100-mile) business passenger trips are made by car, while 78% of the long distance business travelers sampled for the study were traveling by air.