Inclusive accessibility: Analyzing socio-economic disparities in perceived accessibility

New paper!  Kar, A., Xiao, N., Miller, H.J. and Le, H.T.K. “Inclusive accessibility: Analyzing socio-economic disparities in perceived accessibility,” Computers, Environment and Urban Systems,  114, 102202

Highlights

  • Inclusive access considers both physical and perceptual barriers to travel.
  • Perceptions of safety and comfort vary with people’s socio-economic statuses.
  • Existing infrastructure and services yield unequal access across communities.
  • High-income white populations experience transportation privileges over others.
  • Low-income communities with greater risk exposures perceive higher mobility barriers.

Abstract

Existing accessibility measures mainly focus on the physical limitations of travel and ignore travelers’ perceptions, behavior, and socio-economic differences. By integrating approaches in time geography and travel behavior, this study introduces a bottom-up inclusive accessibility concept that aggregates individual-level travel perceptions across socio-economic groups to evaluate their multimodal access to opportunities. We classify accessibility constraints into hard constraints (physical space-time limitations to travel) and soft constraints (perceptual factors influencing travel, such as safety perceptions, comfort, and willingness to travel). We categorize travelers into 12 mutually exclusive socio-economic groups from a mobility survey dataset of 477 travelers. We apply a support vector regressor-based ensemble algorithm to estimate network-level walking perception scores as soft constraints for each social group. We derive group-specific inclusive accessibility measures that consider space-time limitations from transit and sidewalk networks as hard constraints and minimize the group-specific soft constraint to a certain threshold. Finally, we demonstrate the effectiveness of group-specific inclusive accessibility by comparing it with the classic access measure. Our study provides scientific evidence on how people of varying socio-economic statuses perceive the same travel environment differently. We find that socio-economically disadvantaged communities experience higher mobility barriers and lower accessibility while walking and using transit in Columbus, OH. Our study demonstrates a transition from person- to place-based accessibility measures by sequentially quantifying mobility perceptions for individual travelers and aggregating them by social groups for a large geographic scale, making this approach suitable for equity-oriented need-specific transportation planning.

 

The built environment and the determination of fault in urban pedestrian crashes: Toward a systems-oriented crash investigation

New paper: Stiles, J. and Miller, H.J. (2024) “The built environment and the determination of fault in urban pedestrian crashes: Towards systems-oriented crash investigation,”  Journal of Transport and Land Use, 17, 97-113.

Abstract: This study identifies built environmental factors that influence the determination of fault in urban pedestrian crashes in the United States, with implications for both safety and equity. Using data from Columbus, Ohio, we apply regression modeling, spatial analysis, and case studies, and find pedestrians are more likely to be found at fault on fast, high-volume arterial roads with bus stops. We also observe that better provision of crossings leads to more marked intersection crashes, which are less likely to be blamed on pedestrians. In addition, large differences in both the provision of crossings and fault exist between neighborhoods. We interpret findings through the lenses of the systems-oriented safety approaches Safe Systems and Vision Zero. The conclusion argues that the designation of individual responsibility for crashes preempts collective responsibility, preventing wider adoption of design interventions as well as systemic changes to the processes that determine the built environment of US roadways.

Media

Transportation geography group at The Ohio State University

Some of the mighty transportation geographers (and alumni) at The Ohio State University.

(L-R): Ruochen Yin (PhD student), Ahmad Tokey (PhD student), Aniket Sangwan (PhD student), Huyen T.K. Le (Assistant Professor), Armita Kar (PhD, 2023; post-doc at Nationwide Children’s Hospital, Columbus), Luyu Liu (PhD, 2023; post-doc at University of Florida),  Abdirashid Dahir (PhD student), Harvey Miller (Professor)

Not shown but in our hearts: Sara Johnson (PhD student), John Layman (Masters student), Manhoush Mostafavi Sabet (PhD student)