published journal article
working paper
This research concerns the relationships between the patterns of activities pursued in home-based trip chains and the characteristics of the persons making the chains. The data source is a one-week travel diary reported by persons over eleven years of age in the Netherlands in 1984. All home-based trip chains, including both simple two-link chains and more complex ones, were classified on the basis of the sequence of away-from-home activities. Twenty types were distinguished. The presence or absence of these trip-chain types were then explained in terms of the personal and household characteristics of the travellers using non-linear canonical correlation analysis. This analysis technique can accommodate multiple dependent variables and nominally-scaled (categorical) variables in both the independent and dependent variable sets. Determined are the category scores for each independent variable that are optimal in explaining patterns in the dependent chain-type variables. Also determined are the optimal combinations of the two variable sets. These results capture the relationships between the sequences of activities in trip chains and the variables age, sex, working status, household income, stage in the family life cycle, household car ownership, and residential location. The most effective variable was found to be life cycle, followed by age and income.
conference paper
published journal article
Systematic lane changes can seriously deteriorate traffic safety and efficiency inside lane-drop, merge, and other bottleneck areas. In our previous studies (Jin, 2010a, Jin, 2010b), a phenomenological model of lane-changing traffic flow was proposed, calibrated, and analyzed based on the concept of lane-changing intensity. In this study, we further consider weaving and non-weaving vehicles as two commodities and develop a multi-commodity, behavioral Lighthill-Whitham- Richards (LWR) model of lane-changing traffic flow. Based on a macroscopic model of lane-changing behaviors, we derive a fundamental diagram with parameters determined by car-following and lane-changing characteristics as well as road geometry and traffic composition. In particular, we calibrate and validate fundamental diagrams corresponding to a triangular car-following fundamental diagram with NGSIM data. We introduce an entropy condition for the multi-commodity LWR model and solve the Riemann problem inside a homogeneous lane-changing area. From the Riemann solutions, we derive a flux function in terms of traffic demand and supply. Then we apply the model to study lane-changing traffic dynamics inside a lane-drop area and show that the smoothing effect of HOV lanes is consistent with observations in existing studies. The new theory of lane-changing traffic flow can be readily incorporated into Cell Transmission Model, and this study could lead to better strategies for mitigating bottleneck effects of lane-changing traffic flow.
working paper
This chapter describes how transportation demand is analyzed and what has been learned from doing so. We first present a selection of the most important transportation demand models, with an emphasis on disaggregate models because they have generally been the most successful in capturing essential features of travel behavior. We then show how the models have enriched our substantive knowledge of the demand for transportation, and discuss how they have been used to address important transportation policy issues.
MS Thesis
The main objective of this thesis is to highlight the travel patterns of two-person households in California as captured in the 2000-2001 and 2010-2012 California Household Travel Surveys (CHTS). The intent is to present basic travel characteristics of households with two peoples who are couples, are employed and do not have kids at home (denoted as DINK – Dual Income No Kids at home) along with comparisons with two-person households who does not belong to the aforementioned category (NON-DINK) using the CHTS 2000-2001 and 2010-2012 datasets. The results highlight significant differences in travel patterns between the two categories, DINKs and NON-DINKs during the eleven years from 2001 to 2012. The average number of daily trips is higher for DINKs compared to NON-DINKs and the trip rate has reduced in 2012 compared to 2001 for both categories. Auto (driver of auto/truck/van) trips is the primary mode of travel for DINKs and NON_DINKs in CHTS 2001 and 2012. During the eleven years, there has been a decrease in auto trips and an increase in the percentages of passenger, bike, walk and transit trips. The primary trip purpose for DINKs are work or work-related, whereas the primary trip purpose for NON-DINKs are shopping/maintenance trips according to both survey results.
published journal article
published journal article
(1) Background: Human activity is warming the planet and destabilizing the climate through greenhouse gas emissions, which underscores the need for climate communication to overcome barriers to action. (2) Methods: We launched a five-month campaign that included questionnaires (n = 500) and one-on-one interviews (n = 24) to assess climate change sentiment, engagement, adaptation, as well as understand who climate outreach reaches and the observations and concerns such groups report across the U.S. so as to better understand the local context of climate change and enable more effective climate communication and outreach in the future. (3) Results: Results showed outreach efforts to mostly reach college educated Caucasians who identified as Democrats. “Future generations” was the most frequently ranked climate concern, with the economy, property value, and national security ranked last. Communities frequently observed hotter temperatures, increased flooding, and species impacts. Among “climate-concerned” individuals, the majority reported never contacting a local politician about climate change. College students least frequently reported climate change as a top priority and reported a low frequency of civic engagement on the issue. In-person interviews highlighted climate impacts disproportionately affecting low-income communities and communities of color, such as heat-related mortality and gentrification. Climate adaptation strategies were underway, but mostly among farmers, ecologists, and non-governmental organizations (NGO) workers. (4) Discussion: This study helps inform elected officials, urban planners, and climate communicators as it relates to the allocation of resources for climate adaptation and education, and highlights key knowledge gaps that deserve focus by future outreach efforts.
working paper
The objective of the present study is to identify relationships that exist among: (i) intentions to purchase alternative-fuel vehicles prior to their large-scale introduction, (ii) attitudes toward the environment, (iii) perceived importance of convenience and economy of ownership and operation, and (iv) consumer uncertainties. The intent is to unveil what factors, if any, may impede the promotion of alternative fuels, and, in turn, offer some guidelines for successful marketing of alternative-fuel vehicles. The study results can also aid in future stated preference demand estimation surveys by identifying factors that are likely to play important roles in the purchase of alternative vehicles.
conference paper