Value of Time Comparisons in the Presence of Unexpected Delay.

This study estimates Value of Time differences between people who arrived at their destination as planned and those that were delayed. The analysis is based on the I-394 MnPASS High Occupancy/Toll (HOT) lane project recently implemented in the Minneapolis/St. Paul region. Using a Stated Preference survey, the individuals are asked about a trip they have taken before, and asked if they would opt for the free route or pay and go on the HOT lanes. The analysis groups the travelers into subscribers and non-subscribers of the MnPASS (electronic toll collection transponder) system and further decomposes choices into categories based on trip time and experience (delayed or not). Trip times were divided into morning peak, afternoon peak, and off peak and trip experience was divided into delayed and not delayed, creating six categories. The findings suggest an increased willingness to pay among subscribers who were late to reduce travel time in the PM rush hour. As well, we find some evidence that individuals who were late during the AM peak have a lower VOT as compared to their on-time counterparts.Travel time reliability, Stated preference, delay, high occupancy vehicle, high occupancy toll lane

Work and Home Location: Possible Role of Social Networks

This research explores to what extent people's work locations are similar to that of those who live around them. Using the Longitudinal Economic and Household Dynamics data set and the US census for the Twin Cities (Minneapolis-St. Paul) metropolitan area, we investigate the home and work locations of different census block residents. Our aim is to investigate if people who live close to one another, also work close to one another to a degree beyond what would be expected at random. We find a significantly non-random correlation between joint home and joint work locations. Further, we show what features of particular neighborhoods are associated with comparatively higher incidences of people sharing work locations. One reason for such an outcome can be the role neighborhood level social networks play in locating jobs; or conversely work place social networks play in choosing the home location or both. Such findings should be used to refine work trip distribution models that otherwise depend mainly on impedance between the origin and destination.Social Networks, Trip Distribution, Destination Choice, Work, Commuting, Residential Location

Contacts and Meetings: Location, Duration and Distance Traveled

The role of contacts on travel behavior has been getting increasing attention. This paper reports on data collected on individualÕs social meetings and the choice of in-home/out-of-home meeting locations as well as the distance travelled and duration of out-home-meetings and its relationship to the type of contact met and other attributes of the meeting. Empirically we show that in-home meetings tend to occur most often with close contacts and less often with distant contacts. The purpose, meeting day, and household size suggest that leisure, weekend and large household size people tend to have their meetings either at their home or at their contactÕs home. In addition when meetings occur outside of the house, the duration is longer for close contacts and distance to the meeting location is directly inßuenced by duration and indirectly by the relationship type. Overall the paper illustrates that relationship type along with other meeting speciÞc and demographic variables is important in explaining the location, duration and distance travelled for social meetings.Travel behavior, social networks, meetings, network analysis

Selfishness and Altruism in the Distribution of Travel Time and Income

Most economic models assume that individuals act out their preferences based on their own self interest. However there have also been other paradigms in the economics literature that have tried to capture alternative manifestations of human behavior that include fairness. This study examines people's preferences when it comes to their travel time and their income and what type of trade offs they are willing to make to live in a society where the distributions of travel time and income are fairer. Using a stated preference experiment we find that when it comes to travel time, individuals are more concerned with societal average travel time, followed by their own travel time and finally by large inequalities in the society, while in the case of income they are more concerned with their own income, followed by societal average and finally by inequality.Fairness, Inequality, Travel Time, Income, Altruism, Stated Preference, Veil of ignorance, Equity, Time equity, Income Equity, Time distribution, Income Distribution.

I-35W Bridge Collapse: Travel Impacts and Adjustment Strategies

On August 1st, 2007, the I-35W bridge crossing the Mississippi river fell into the Mississippi river. In addition to the human tragedy that it caused, the bridge failure also impacted how people moved in the area. The bridge carried 140,000 cars daily. As such it required a significant amount of traffic find new routes to reach their destinations. Traffic impacts may also have led to changes in mode, time, or some trips being foregone. Those who changed routes were not just the ones that previously used the bridge. With the I-35 traffic using alternate routes, those who saw or anticipated higher traffic also found it necessary to re route their trips. In this study we ask a sample of people that were recruited for another study, if their travels had been impacted by the failure of the bridge, how they coped and what impacts it had on their travels and other activities.I-35W Bridge, Minnesota, Minneapolis, Travel Behavior

A Moment of Time: Reliability in Route Choice using Stated Preference

Understanding how reliability is valued is important because it provides insight to how aims of policies that aspire to provide better transport options can be more fully integrated with user expectations. In this study we derive a choice model for work commute trips that trades off alternatives based on the most frequent experience that users had on that route and the possibility of late or early arrival if they use a particular route. The idea of reliability is incorporated by how far the expected lateness or early arrival is from the most frequent experience on that route. We find that on route decisions the mode travel time is valued at $7.43 per hour while reduction from the magnitude of average lateness (thereby increasing the reliability of the route) is valued at$6.91 per hour.Travel time reliability, Stated preference, Late Penalty, Early Penalty

Home Relocation and the Journey to Work

Relocation decisions are complex. Each household has a bundle of attributes that make a location attractive to it, including the ability to access different activity locations easily, neighborhood quality, house amenities etc. Relocating households have an opportunity to Þnd housing closer to their work. Using data collected in the Twin Cities area, we investigate how distance to home and travel time to home change among individuals who have changed their residence since they started their current job. Comparing the home-to-work distance after the move to the previous-home-to-work distance, we Þnd that the average home to work distance is reduced as a result of the move. We also Þnd that the reduction depend on the previous home to work distance as well as the previous homesÕ proximity to downtown Minneapolis. The Þndings show that households that are either very close to their work, or very close to down- town, or both did not signiÞcantly increase or decrease their commute after relocation. This suggests that access to work as well as access to the opportunities that proximity to downtown offers (to jobs, urban spaces, etc.) are important in the decision making process.Journey to Work, Commuting, Relocation, Tenure, Jobs, Minnesota, Minneapolis

The Role of Job Search Methods and Contacts on Commuting and Relocation Decisions

This paper empirically explores the relationship between (i) job finding and commuting outcomes and (ii) the relationship between job search and the commute and location outcomes of relocation decisions after finding employment. The relationship between commute outcomes when finding a new job and the job search method that one employs are explored first. That is followed by an analysis of how long one stays at their residence after finding work, and where they eventually relocate relative to their new employment site as well as their previous residence. Along with the usual socio-demographic variables, the analysis takes on the job search method as well as the local contacts that one has in their residential area as important variables informing these choices. The findings indicate that jobs found through the use of internet and newspapers were on average farther away from the searchersÕ residence as compared to those found through contacts and formal means. On relocation after employment, we find that being a renter and moving to a rental unit were important in how quickly one relocated. In addition those that used the internet to find their jobs also relocated faster after controlling for demographic variables such as age. The distribution of ones social contacts were also found to be important in how far away from the previous location a person relocated.Job search, travel behavior, transport geography, commuting, relocation

Effects of Mode Shares on Mode Choice

This study considers the influence of the knowledge of existing mode shares on travelers mode choice. This contrasts with traditional mode choice models, where the main objective is to predict the overall mode shares as the aggregate of individual mode choices according to variables encompassing attributes of the modes, and characteristics of the travelers. In this study, a computer-administered adaptive stated preference survey is developed and applied to a sample of subjects selected from the University of Minnesota. The results indicate that the presence of mode shares in the mode choice model does influence the decision of travelers.mode choice, mode shares, mixed logit, stated preference.

Incorporating weather information into real-time speed estimates: comparison of alternative models

Weather information is frequently requested by travelers. Prior literature indicates that inclement weather is one of the most important factors contributing to traffic congestion and crashes. In this paper, we propose a methodology to use real-time weather information to predict future speeds. The reason for doing so is to ultimately have the capability to disseminate weather-responsive travel time estimates to those requesting information. Using a stratified sampling technique, we select cases with different weather conditions (precipitation levels) and use a linear regression model (called the base model) and a statistical learning model (using Support Vector Machines for Regression) to predict 30-minute ahead speeds. One of the major inputs into a weather-responsive short-term speed prediction method is weather forecasts; however, weather forecasts may themselves be inaccurate. We assess the effects of such inaccuracies by means of simulations. The predictive accuracy of the SVR models show that statistical learning methods may be useful in bringing together streaming forecasted weather data and real-time information on downstream traffic conditions to enable travelers to make informed choices