The effects of neighborhood characteristics and the built environment on pedestrian injury severity: A random parameters generalized ordered probability model with heterogeneity in means and variances Chunfu Xin a,⇑ , Rui Guo b , Zhenyu Wang c , Qing Lu d , Pei-Sung Lin c a Department of Civil and Environmental Engineering, University of South Florida, 4202 E. Fowler Avenue, ENC2006, Tampa, FL 33620, United States b Civil, Environmental, and Construction Engineering (CECE), Texas Tech University, 2500 Broadway, Lubbock, TX 79409, United States c Center for Urban Transportation Research, University of South Florida, 4202 E. Fowler Avenue, CUT100, Tampa, FL 33620, United States d Department of Civil and Environmental Engineering, University of South Florida, 4202 E. Fowler Avenue, ENC3002, Tampa, Florida, USA article info Article history: Received 3 July 2017 Received in revised form 6 October 2017 Accepted 6 October 2017 Keywords: Pedestrian injury severity Neighborhood characteristics Built environment Generalized ordered probability model Unobserved heterogeneity abstract Transportation infrastructure facilities and pedestrian/driver behaviors are associated with neighborhood characteristics and the built environment. However, the effects of neighbor- hood characteristics and the built environment on pedestrian injury severity are not well documented. To investigate and quantify the effects of neighborhood characteristics and built environment on pedestrian injury severity, a random parameters generalized ordered probit model with heterogeneity in means and variances was proposed to consider the ordinal nature of injury data and the issue of threshold and unobserved heterogeneity. A total of 3867 pedestrian-vehicle crashes that occurred in Florida Department of Transportation District 7 from 2011 to 2014 were analyzed. Based on the estimation results, three factors (African American community, school zone, and bus stop area) related to neighborhood characteristics and the built environment were identified to have signif- icant influence on pedestrian injury severity. Pedestrian-vehicle crashes that occurred in African American community or bus stop area are less likely to involve incapacitating and fatal injuries. The presence of a school within a 0.5-km buffer from a crash leads to a decreased probability of fatal injury and an increased probability of incapacitating injury. In addition, the estimated parameter for elderly pedestrian indicator (50 < age  65) was found to be random with significant heterogeneity in both mean and variance (where the mean and variance are associated with intersection-related crash indicator). Compared to younger pedestrians (age  30), 74.3% of elderly pedestrians who are involved in intersection-related crashes are more likely to suffer severe injury (fatal or incapacitating injury), while 52.4% of elderly pedestrians who are not involved in intersection-related crashes are more likely to suffer severe injury. Ó 2017 Elsevier Ltd. All rights reserved. https://doi.org/10.1016/j.amar.2017.10.001 2213-6657/Ó 2017 Elsevier Ltd. All rights reserved. ⇑ Corresponding author. E-mail addresses: chunfu@mail.usf.edu (C. Xin), rui.guo@ttu.edu (R. Guo), zwang9@cutr.usf.edu (Z. Wang), qlu@usf.edu (Q. Lu), lin@cutr.usf.edu (P.-S. Lin). Analytic Methods in Accident Research 16 (2017) 117–132 Contents lists available at ScienceDirect Analytic Methods in Accident Research journal homepage: www.elsevier.com/locate/amar