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Drivers receive value from traveler information in several ways, including the ability to save time, but perhaps more importantly, from certainty, which has other personal, social, safety, or psychological impacts. This project aims to quantify travelers' willingness to pay for pre-trip travel-time information on alternative routes. Different from previous studies based only on stated preference surveys, the 117 participants in the current study actually drove real-world routes. Pre-trip travel-time information was provided in the field experiment to half the participants. Various data collection techniques were used including in-vehicle GPS units, pre- and post-experiment surveys, and travel diary. Results reveal that speed and efficiency are not the only dimensions on which people make route choices. Ease of driving, pleasantness, and the presence of information are also significant factors. Results from multinomial and rank-ordered logit models indicate that many travelers receive value of up to $1 per trip for pre-trip travel-time information. The value of this information is higher for commuting, special event trips, and when there is heavy congestion. The accuracy of the travel-time information is crucial - it is only useful if it is believed to be accurate.

Traffic congestion has become an increasingly serious problem in many cities. Ramp metering, which maintains smooth freeway mainline flow by limiting vehicle entry at entrance ramps, has been proposed and implemented in a number of metropolitan areas in and outside the U.S. to mitigate freeway congestion. This study aims to develop both efficient and equitable freeway ramp control strategies. Traffic conditions with and without ramp metering are evaluated on several representative freeways in the Twin Cities with a comprehensive set of performance measures. A unified theory for ramp metering is proposed based on a linear programming model of freeway traffic dynamics. The most efficient ramp control algorithm is found to be also the least equitable one. A novel control objective, minimizing weighted or perceived travel time, is therefore proposed to balance efficiency and equity objectives of ramp metering. This research also develops a new family of applicable ramp metering strategies, which consider both efficiency and equity, and are demonstrated in a microscopic traffic simulator. Future studies should compare various traffic control methods under the analytical framework proposed in this report. Researchers should also pursue field experiments of the proposed multi-objective ramp control strategies.