Route Choice.

Prediction of the Deviation between Alternative Routes and Actual Trajectories for Bicyclists

| David Levinson

Recently published:

  • Wang, Haotian, Emily Moylan, and David M. Levinson (2022) “Prediction of the Deviation between Alternative Routes and Actual Trajectories for Bicyclists.” Findings, June. [doi].

This study estimates a panel regression model to predict bicyclist route choice. Using GPS trajectories of 600 trips from 49 participants in spring 2006 in Minneapolis, we calculate deviation, the average distance between alternative routes and actual trajectories, as the dependent variable. Trip attributes, including trip length, Vehicle Kilometres Travelled (VKT), the number of traffic lights per kilometer, and the percentage of bike trails and separated bike lane, are included as independent variables. F-tests indicate that both fixed entity and time effect panel regression models offer better fits than the intercept-only model. According to our results, routes with shorter length and higher share of bike trails tend to have less deviation in their trajectories. Traffic lights per km, VKT, and share of bike lane are not significant at the 95% confidence level in this data set.

Figure 1. Example of Commute and Non-Commute Trips

An Agent-based Route Choice Model with Learning and Exchange of Information

| David Levinson

Recently published

Abstracturbansci-02-00058-g001-550

Planning models require consideration of travelers with distinct attributes (value of time (VOT), willingness to pay, travel budgets, etc.) and behavioral preferences (e.g., willingness to switch routes with potential savings) in a differentiated market (where routes have varying tolls and levels of service). This paper proposes to explicitly model the formation and spreading of spatial knowledge among travelers, following cognitive map theory. An agent-based route choice (ARC) model was developed to track choices of each individual decision-maker in a road network over time and map individual choices into macroscopic flow pattern. ARC has been applied to both the Sioux Falls and Chicago sketch networks. Comparisons between ARC and existing models (user equilibrium (UE) and stochastic user equilibrium (SUE)) on both networks show ARC is valid and computationally tractable. In brief, this paper specifically focuses on the route choice behavior, while the proposed model can be extended to other modules of transportation planning under an integrated framework.

Keywords: agent-based model; route choice; traffic assignment; travel demand modeling

An empirical study of the deviation between actual and shortest travel time paths

| David Levinson

Recently published

DeviationAbstract: This study evaluates routes followed by residents of the Minneapolis–St. Paul metropolitan area, as measured by the Global Positioning System (GPS) component of the 2010/11 Twin Cities Travel Behavior Inventory (TBI). It finds that most commuters used paths longer than the shortest path. This is in part a function of trip distance (+, longer distance trips deviate more), trip circuity (−, more circuitous trips deviate less), number of turns (+, trips with more turns per kilometer deviate more), age of driver (−, older drivers deviate less), employment status (+, part-time workers deviate more), flexibility in work hours (+, more flexibility deviate more), and household income (−, higher-income travelers deviate less). Some reasons for these findings are conjectured.

Author keywords: Global positioning system (GPS); Shortest path; Route choice; Wardrop’s principles; Travel behavior.

Indifference Bands for Route Switching

| David Levinson

Printed, (after more than a year in “online first” purgatory) and now available for FREE Viewing.11116_2016_9699_Fig3_HTML

Abstract: The replacement I-35W bridge in Minneapolis saw less traffic than the original bridge though it provided substantial travel time saving for many travelers. This observation cannot be explained by the classical route choice assumption that travelers always take the shortest path. Accordingly, a boundedly rational route switching model is proposed assuming that travelers will not switch to the new bridge unless travel time saving goes beyond a threshold or “indifference band”. To validate the boundedly rational route switching assumption, route choices of 78 subjects from a GPS travel behavior study were analyzed before and after the addition of the new I-35W bridge. Indifference bands are estimated for both commuters who were previously bridge users and those who never had the experience of using the old bridge. This study offers the first empirical estimation of bounded rationality parameters from GPS data and provides guidelines for traffic assignment.

Keywords:

Bounded rationality, Indifference band, Empirical estimation, GPS study, Route Choice

 

An empirical study of the deviation between actual and shortest travel time paths

| David Levinson

Shortest distance and time route vs. actual route for one person on one day.
Shortest distance and time route vs. actual route for one person on one day.

Recent working paper:

Few empirical studies of revealed route characteristics have been reported in the literature. This study challenges the widely applied shortest-path assumption by evaluating routes followed by residents of the Minneapolis–St. Paul metropolitan area, as measured by the GPS Component of the 2010 Twin Cities Travel Behavior Inventory conducted by the Metropolitan Council. It finds that most travelers used paths longer than the shortest path. This is in part a function of trip distance, trip circuity, number of turns, and age of the driver. Some reasons for these findings are conjectured.

Indifference Bands for Route Switching

| David Levinson

Recent working paper:

Di, X, Liu, H, Zhu, S, and Levinson, D. (2014) Indifference Bands for Route Switching

Frequency of Switchers and Stayers vs. Travel Time Saving Percentage
Frequency of Switchers and Stayers vs. Travel Time Saving Percentage

  • Abstract: The replacement I-35W bridge in Minneapolis saw less traffic than the original bridge though it provided substantial travel time saving for many travelers. This observation cannot be explained by the classical route choice assumption that travelers always take the shortest path. Accordingly, a boundedly rational route switching model is proposed assuming that travelers will not switch to the new bridge unless travel time saving goes beyond a threshold or “indifference band”. To validate the boundedly rational route switching assumption, route choices of 78 subjects from a GPS travel behavior study were analyzed before and after the addition of the new I-35W bridge. Indifference bands are estimated for both commuters who were previously bridge users and those who never had the experience of using the old bridge. This study offers the first empirical estimation of bounded rationality parameters from GPS data and provides guidelines for traffic assignment.
    Keywords: Route Choice, Travel Demand Modeling, Bounded Rationality, Indifference Band, GPS Study, Travel Behavior, Networks

“Explaining the Irrational Commuter” in Symposium Magazine

| David Levinson

Traffic moves along a street at night in the Shinjuku distri

I have a post up at Symposium Magazine on “Explaining the Irrational Commuter“. Read it. This article summarizes much of our experimental-behavioral work on route choice decision making over the past decade.

The increasing sophistication of data collection and analysis gives us deeper insights into human behavior — and how we make decisions about everyday travel.

Transportation debates, from the local to national level, are invariably waged between competing interests. There are players representing economic development, road construction, the environmental lobbies, and diverse groups of transportation users — just to name a few. But there is also an important role for independent experts to play — not just as honest brokers, but as analysts who can assess what they learn from the increasingly sophisticated collection of data about travel and human behavior. And this is where academics can step in. Research that I have conducted with colleagues at the University of Minnesota has allowed us break down travel behavior and draw some surprising lessons that can guide transportation policy.

Symposium is a relatively new venue, aimed at building bridges across disciplinary domains in the academy.

Other articles in the issue include:

Thomas Flores on the rise of technocrats; Scott Taylor on what historians can teach us about climate change; Chuck McCutcheon on how one law professor has played a part in both sides of the surveillance debate; and Judith Sebesta on whether college really is for everyone.

The Roads Taken: Theory and Evidence on Route Choice in the wake of the I-35W Mississippi River Bridge Collapse and Reconstruction

| David Levinson

19249-thumb-400x268-56595Congratulations to soon-to-be Dr. Shanjiang Zhu (September 2010- PhD Civil Engineering) for completing and successfully defending his Ph.D Dissertation –
The Roads Taken: Theory and Evidence on Route Choice in the wake of the I-35W Mississippi River Bridge Collapse and Reconstruction He will be joining the University of Maryland, College Park as a post-doc.
Abstract:

Route choice analysis investigates the path travelers follow to implement their travel plan. It is the most frequent, and thus arguably the most important decision travelers make on a daily basis. Long established efforts have been dedicated to a normative model of the route choice decision, while investigations of route choice from a descriptive perspective have been limited. Wardrop’s first principle, or the shortest path assumption, is still widely used in route choice models. Most recent route choice models, following either the random utility maximization or rule-based paradigm, require explicit enumeration of feasible routes. The quality of model estimation and prediction is sensitive to the appropriateness of the consideration set. However, few empirical studies of revealed route characteristics have been reported in the literature. Moreover, factors beyond travel time, such as preferences for travel time reliability, inertia in changing routes, and travel experience that could also have significant impacts on route choice, have not been fully explored and incorporated in route choice modeling. The phenomenon that people use more than one route between the same origin and destination during a period of time is not addressed by conventional route choice models either.
To bridge these gaps, this dissertation systematically evaluates people’s route choice behavior using data collected in the Minneapolis – St. Paul metropolitan area after the I-35W Bridge Collapse. Both aggregate traffic data and individual survey data show gaps between models based on shortest travel time assumption and traffic conditions observed in the field. This study then employs the individual GPS trajectory and GIS maps to systematically evaluate the characteristics of routes people actually use. Merits of route choice set generation algorithms widely used in practice are assessed. The phenomenon of route diversity is clearly revealed through analysis of field data. A route portfolio model is proposed to explain the rationale of choosing a portfolio of routes under uncertainty about network conditions. It is posited that a rule-based model,
comprehensively considering travelers’ characteristics, additional network metrics, and previous travel experience will better replicate observed route choices than the tradi- tional assumption of simply minimizing travel time or travel cost. Findings from this dissertation could also inform other parts of travel demand modeling.

Value of Reliability: High Occupancy Toll Lanes, General Purpose Lanes, and Arterials

| David Levinson

Recent working paper:

In the Minneapolis-St. Paul region (Twin Cities), the Minnesota Department of Transportation (MnDOT) converted the Interstate 394 High Occupancy Vehicle (HOV) lanes to High Occupancy Toll (HOT) lanes (or MnPASS Express Lanes). These lanes allow single occupancy vehicles (SOV) to access the HOV lanes by paying a fee. This fee is adjusted according to a dynamic pricing system that varies with the current demand. This paper estimates the value placed by the travelers on the HOT lanes because of improvements in travel time reliability. This value depends on how the travelers regard a route with predictable travel times (or small travel time variability) in comparison to another with unpredictable travel times (or high travel time variability). For this purpose, commuters are recruited and equipped with Global Positioning System (GPS) devices and instructed to commute for two weeks on each of three plausible alternatives between their home in the western suburbs of Minneapolis eastbound to work in downtown or the University of Minnesota: I-394 HOT lanes, I-394 General Purpose lanes (untolled), and signalized arterials close to the I-394 corridor. They are then given the opportunity to travel on their preferred route after experiencing each alternative. This revealed preference data is then analyzed using mixed logit route choice models. Three measures of reliability are explored and incorporated in the estimation of the models: standard deviation (a classical measure in the research literature); shortened right range (typically found in departure time choice models); and interquartile range (75th – 25th percentile). Each of these measures represents distinct ways about how travelers deal with different sections of reliability. In all the models, it was found that reliability was valued highly (and statistically significantly), but differently according to how it was defined. The estimated value of reliability in each of the models indicates that commuters are willing to pay a fee for a reliable route depending on how they value their reliability savings.