This presentation will explain how researchers used a zero-inflated negative binomial (ZINB) model to predict the accidents at rail grade crossings. The goal of the project was to improve predictions over the current state-of-practice USDOT accident prediction formula. As part of this work, three ZINB models were generated for three different categories of warning devices: gates, flashing lights, and crossbucks. Like the USDOT formula, the direct predictions from the models were adjusted using accident history data. Empirical Bayes (EB) adjustment was applied to ZINB models to improve the predictions.

Data for Illinois were used to develop the models, and data for four other states were used for model validation. Different comparisons were then made between the models. The comparisons show that the ZINB model with EB adjustment outperformed other models because it had a cumulative accident distribution that closely represents the field data. Plots of actual accident counts versus predicted accident counts for each of the models showed that the EB-adjusted accident prediction value is closer to the actual accident counts than the other models. Also, more accurate predictions from the EB-adjusted ZINB model were observed for the top 10, 20, 30, 40, and 50 locations with highest accident frequency from each warning device category. In each of the three comparisons, the EB-adjusted ZINB model outperformed the USDOT model.

What is livability? How does the built environment influence resident perceptions of livability? Although livability is a broadly used term and a key goal in land use and transportation plans at the state level, it is unclear whether residents think their neighborhoods are livable and what contributes to their perception of livability. The purpose of the project was to understand how Oregonians, in neighborhoods of varying densities and within Metropolitan Planning Organizations (MPOs), perceive livability at the nexus of transportation and land use. We sought to understand how residents define and perceive livability in three different MPOs in the state: Albany, Central Lane, and Rogue Valley. Our survey instrument included questions about livability, satisfaction, housing choice, and preferred and current characteristics of the neighborhood and accessibility. 

We found that perceptions were more influential in describing livability than objective or sociodemographic measures. We found that people tradeoff affordability and livability. When people said that housing affordability was more important in decisions about housing and neighborhood choice, they had more negative perceptions of livability in their neighborhood. But people who prioritize accessibility have a more positive perception of livability. Individuals that reported better access to transportation options across a broad range of measures reported higher ratings of livability. Pedestrian improvements and natural amenities were important to survey respondents. Finally, objective and subjective measures of density negatively impacted perceptions of livability. 

The seminar will discuss the findings of this work and takeaways for planners at the local, regional, and state level.

Automated vehicles have the potential to significantly transform the nation's roadways. They offer potential benefits in safety but also introduce uncertainty for the agencies responsible for the planning, design, construction, operation, and maintenance of the roadway infrastructure. The Federal Highway Administration (FHWA) is initiating a national conversation with partners and stakeholders to better understand the implications of highway automation, to facilitate innovation, and to enable broader collaboration in this area. This National Dialogue on Highway Automation will commence with a series of meetings held across the country to facilitate information sharing, identify key issues, and prepare the broader transportation community to safely and efficiently integrate automated vehicles into the road network. Input received during the National Dialogue will help inform national research, policy, and programs and will aid in the development of a national transportation community for automation.

This webinar will provide an overview of the upcoming National Dialogue meetings, discuss ongoing and planned national initiatives in automation, and present top highway automation focus areas to be explored through the Dialogue. Speakers will include key FHWA officials in automation and representatives from partner organizations. Participants will also have an opportunity to provide input during the webinar.