This dissertation includes three essays on Transportation Economics, which studies two important questions in Transportation Economics: first, what are the effects of public investment in transportation infrastructure and provision of transportation goods? and second, how the market mechanism can improve the provision of transportation goods? Chapter one and two address the first question and chapter three addresses the second question. In the first chapter, using disaggregated data on highway construction projects from the California Department of Transportation from 2001 to 2013 and matching project locations with traffic data, I investigate the effect of highway construction projects on reducing congestion. The average effect of spending per mile of highway on both average speed and the traffic flow for the affected highway segments is positive. The increase in speed for morning and evening peak hours is between 0.30-0.45 mph, which accounts for 20 thousand saved hours per day. The reduction in travel time alone accounts for a $1.06 billion benefit over a 30-year period. This amount is equivalent to 60 percent of the total project cost and does not include the reduction in vehicle accidents, travel time reliability, and the effect on users of alternative routes. In the second chapter, I empirically investigate the effects of highway lane closure due to construction activity on user cost. I use data from the California Department of Transportation (Caltrans) on locations and times of lane closures. These data are matched with disaggregated traffic data on hourly traffic speed and flow for each day for most traffic detectors over California highways. I then estimate a fixed effect model of the effects of lane closures on hourly average speed and hourly traffic flow. The results show heterogeneous effects of lane closures on different hours of the day. With most closures occurring over night, between 10 p.m. and 4 a.m., I find a reduction in average speed between 4.5 and 2 mph and an average reduction in the traffic flow of 258 vehicles per hour. I find social costs of lane closures to motorists that are well below the lane late reopening penalties imposed by Caltrans. In the third chapter, I investigate the effect of the SFpark project, a parking experiment on drivers' behavior that was conducted from April 2011 to May 2013 in San Francisco. Using hourly data on occupancy rates of on-street parking, I estimate the responsiveness of commuters to price changes at the block level that vary across locations and time of day. I use a fixed effects model to estimate the elasticity of the occupancy rate with respect to price changes. Moreover, I employ a regression continuity design (RDD) to estimate the effect of different price changes on demand. The elasticities range between -0.13 to -0.44 and vary by time of day and level of occupancy rate.

To provide a more in-depth analysis of potential roadway projects, the Utah Department of Transportation (UDOT) desired a method of evaluating projects according to their economic potential without using potentially costly computer models or excessive data collection. Brigham Young University (BYU) was retained to research and recommend criteria for the economic development criteria in the project-prioritization process. A literature review was first undertaken to better understand the transportation-economic development relationship. Using the literature review, combined with the information from the Economic Development Corporation of Utah, the Governor's Office of Planning and Budget, the Governor's Office of Economic Development, and a Technical Advisory Committee (TAC), criteria were established to evaluate the economic potential of a roadway project. The criteria were finalized using a Policy Delphi method that included the Research Team and TAC. The four aggregate criteria and one bonus criterion recommended are: 1) population and education; 2) existing infrastructure; 3) economic attractiveness; 4) tourism; and 5) the bonus: economic choke-points, which allows UDOT regions to specify a prioritized list of projects that could help increase the economic development potential of an area if those projects are built. An evaluation framework was also developed for the economic development criteria. Any project that passes the Tier I analysis is recommended to be subjected to the economic analysis of the Tier II process. The researchers recommend that once a list of passing Tier I projects is received, the list should be sent out to any participating in the expert feedback portion of the economic attractiveness scoring as well as to the UDOT regions and districts for choke-point prioritization analysis. All of the databases will be updated to provide the most up-to-date scoring possible. When all of the scores have been assigned, the projects will then be listed by highest to lowest scores. The list will then be compiled by UDOT who will present the information to the Transportation Commission in a manner that will best assist in the decision-making process. The research created a scoring evaluation for each recommended criterion. Each criterion also received a weighting. The scoring and the framework are recommended to UDOT as the economic analysis of the Tier II evaluation. The criteria are recommended to be automated in a geographic information systems (GIS) database to aid in the scoring process.

Transportation economists apply different labor supply models when studying anti-congestion policy: (i) endogenous working hours; (ii) endogenous workdays but given daily working hours; (iii) labor supply as a residual. We study whether the outcome of anti-congestion policies that change the relative cost of labor supply margins, and, thus, may affect decisions on working hours and working days, is robust against the model applied. In particular, we focus on welfare implications in the presence of other taxes when there is a congestion externality. We find surprisingly strong differences in quantity and sign. Further, we develop a clear recommendation for future research on issues that include decisions on commuting trips. Researchers shall apply both a model of endogenous working hours that provides an upper limit and a model of endogenous workdays that provide a lower limit of results for welfare changes, optimal policies and two optimal tax components (Pigouvian and Ramsey terms).

This dissertation analyzes the impact of climate, and atmospheric carbon dioxide (CO2) on crop yields and grain transportation. The analysis of crop yields endeavors to advance the literature by statistically estimating the effects of atmospheric carbon dioxide (CO2) on observed crop yields. This is done using an econometric model estimated over pooled historical data for 1950-2009 and data from the free air CO2 enrichment experiments. The main findings are: 1) yields of soybeans, cotton, and wheat directly respond to the elevated CO2, while yields of corn and sorghum do not; 2) the effect of crop technological progress on mean yields is non-linear; 3) ignoring atmospheric CO2 in an econometric model of crop yield likely leads to overestimates of the pure effects of climate change and technological progress on crop yields; and 4) average climate conditions and climate variability contribute in a statistically significant way to average crop yields and their variability. To examine climate change impacts on grain transportation flows, this study employs two modeling systems, a U.S. agricultural sector model and an international grain transportation model, with linked inputs/outputs. The main findings are that under climate change: 1) the excess supply of corn and soybeans generally increases in Northern U.S. regions, while it declines in Central and Southern regions; 2) the Corn Belt, the largest producer of corn in the U.S., is anticipated to ship less corn; 3) the importance of lower Mississippi River ports, the largest current destination for U.S. grain exports, diminishes under the climate change cases, whereas the role of Pacific Northwest ports, Great Lakes ports, and Atlantic ports is projected to increase; 4) the demand for grain shipment via rail and truck rises, while demand for barge transport drops.