| The overall goals of this study are to enhance the fundamental understanding of long-distance travel characteristics in the US, and to provide policy implications for long-distance transportation planning in the future. This study uses the 2009 National Household Travel Survey (NHTS) and state add-on data that provide a daily trip data base in both national and state perspectives. In particular, this study focuses on long-distance trips defining long-distance trip as a trip segment that is 50 or more miles from origin to destination.;In order to achieve the research goal, this study first summarizes current patterns and characteristics of long-distance travel in the United States. In addition, this study develops mode choice models for long-distance travel that can explain the relationship between travelers' choices of transportation mode and a set of explanatory variables such as alternative specific attributes (travel time, travel costs and access/egress time and costs), individual characteristics (income, age, and trip purpose), and geographical characteristics of household (MSA category, and existence of heavy rail service). This study estimates the Multinomial Logit models based on the mathematical function of the Conditional Logit (CL) model.;In order to develop logit models, this study estimates synthetic travel time and costs of all available transportation modes. In estimating synthetic travel time and costs, this study used all possible sources of published data including average driving costs per mile by passenger car type, air passengers fare and flight distance survey, bus and train fare and travel time tables. In addition, this study calculated shortest distance from each household to intercity terminals such as 422 commercial airports, 1482 bus terminals, and 533 train stations.;Finally, this study predicted the probability of choosing a new alternative by applying travel time and costs scenarios to the estimated model. For that, this study assumes a new alternative mode as an improved train system because no other ground modes are able to provide a speed of 200 or more miles. Based on the findings, this study suggests viable options for planners and decision makers to plan for long-distance transportation in the future. |
