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My research focuses on active transport and multimodal aspects of emerging transportation technologies through their impacts on health and safety.

You can also find my work on Google Scholar.  We are always looking for students to help with our research.

Emerging Transportation Technologies


I am examining the relationship between autonomous vehicles and human road users. Focus will be given to the health and safety consequences of emerging transportation technologies. We are using virtual reality to explore the interaction between AVs and pedestrians, bicyclists, and human drivers. This research has been published in Journal of Traffic and Transportation Engineering and Journal of Risk and Uncertainty in Engineering Systems.


Police vs. Hospital Collision Data


I'm working with surgeons at the University of New Mexico Hospital to examine how many collisions are missed in police data and the accuracy of police injury severity diagnoses. We are also using medical diagnoses to explore the safety outcomes of different road designs. This work was published in Accident Analysis & Prevention and is under peer review at Journal of Trauma and Acute Care.


Bike-Friendly Cities and Safety for All Road Users


I investigated the relationship between cycling levels and overall safety within cities' transportation systems. The paper was recently published in Journal of Transport & Health. We are currently working on an analysis of medium-sized cities.

Distribution Equality of Bike Facilities


I analyzed 11,010 lane miles of bike facilities over nine years across 29 U.S. cities to understand how equally facilities are being installed in terms of sociodemographic/socioeconomic characteristics. Findings suggest that non-White neighborhoods experience the lowest rates of installation and the installation of bike facilities leads to higher incomes. This work was published in Transportation Resarch Part D: Transport and Environment. We are also pursuing a similar analysis on the network level.

Vision Zero Analysis


I computed traffic safety outcomes for eighteen U.S. early adoption Vision Zero cities and explored how city characteristics and action plans correlated with those outcomes. Findings highlight issues with automobile-dependence. This work has been published in Transportation Letters.

Pedestrian Safety


Pedestrian fatalities in the U.S. rose 51% between 2009 and 2019, compared to a 0.4% increase in fatalities for all other motor vehicle collisions. My students and I have written multiple papers on the topic, including papers that explore characteristics of these collisions, trends across the injury severity spectrum, and geospatial characteristics of the collisions. These papers have been published in Traffic Injury Prevention and Journal of Safety Research, with several still under peer review.

Wildlife Detection


In collaboration with NMDOT and the NM and AZ Departments of Game & Fish, we captured over 120,000 pictures of nearly 2,000 animals to better understand wildlife vehicle collisions on New Mexico highways.  This work is still under peer review.

Emergency Response Times


We investigated trends in emergency response time to motor vehicle collisions. This paper was recently published in Transportation Research Record.

Bike LTS Validation


We validated the bicycle level of traffic stress metric. This paper was published in Transportation Research Record.

Proactive Traffic Safety on the Trip to School


In order to develop a proactive traffic safety methodology, I am investigating walking and bicycling trips to school in Denver.  By understanding which built environment factors impact  parental perceptions, I am able to measure trips that are suppressed due to safety concerns and thereby proactively identify traffic safety issues.  The work is published in Transportation Research Part A, Travel Behaviour and Society, and Transportation Research Record and has been presented at Congress for the New Urbanism, the National Walking Summit, an ITE Webinar, and other conferences.


Safety of Bicycle Shared Lane Markings


I investigated the effectiveness of shared lane markings ("sharrows") in terms of safety outcomes.  While the initial results received some attention (Streetsblog, Public Radio, and CityLab) after TRB in 2016, the research has been reformulated to include dooring crashes.  The paper has been published in the International Journal of Transportation Science and Technology.

National Adult/Child Bicycling Fatality Trends


I examined national trends in bicycling safety in relation to age and gender of bicyclists from 1985-2015.  Findings show important differences across age groups.  This work was published open-access in Transportation Research Interdisciplinary Perspectives.


Bicycle Safety Performance Functions


​Along with a team from Portland State University and the University of North Carolina, I helped to derive safety performance functions (SPFs) for bicyclists.  These were the first bicycle SPFs for roadway segments in a U.S. city.

Urban/Rural Road Safety


Investigated disparities in road safety outcomes between urban rural settings and different socio-economic groups.  The paper was published in Journal of Urbanism.

Child Pedestrian Traffic Safety and Parks


​I explored traffic safety issues of child pedestrians around parks, identifying best practices for ensuring children have safe access.  Findings were published in Injury Prevention.


Pedestrian Safety in India


As a result of my time with the World Resources Institute in Bangalore, I became interested in examining pedestrian behavior in relation to safety in urban areas of India.  This has resulted in three papers published in Transportation Research Part F, Journal of Traffic and Transportation Engineering, and Journal of Global Epidemiology and Environmental Health.


Motorized Two-Wheelers in India


​I looked at the role of motorized two-wheelers in the Indian transportation system.  This resulted in a published resource, a webinar, and a presentation at TRB.



Commute Mode and Mental Health


​I examined the relationship between mental health and commute mode in major metropolitan areas of the United States.  The findings were published in 2014.

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