Next Article in Journal
Traversing Community Attitudes and Interaction Experiences with Large Agricultural Vehicles on Rural Roads
Previous Article in Journal
What Employees Do Today Because of Their Experience Yesterday: How Incidental Learning Influences Train Driver Behavior and Safety Margins (A Big Data Analysis)
Article

Observations on the Relationship between Crash Frequency and Traffic Flow

1
Deutsches Zentrum für Luft- und Raumfahrt e.V., Institute of Transportation Systems, Rutherfordstrasse 2, D-12489 Berlin, Germany
2
Institute of Land- and Sea Transport Systems, Technical University of Berlin, Salzufer 17-19, D-10587 Berlin, Germany
*
Authors to whom correspondence should be addressed.
Received: 25 October 2020 / Revised: 3 January 2021 / Accepted: 7 January 2021 / Published: 11 January 2021
This work analyzes the relationship between crash frequency N (crashes per hour) and exposure Q (cars per hour) on the macroscopic level of a whole city. As exposure, the traffic flow is used here. Therefore, it analyzes a large crash database of the city of Berlin, Germany, together with a novel traffic flow database. Both data display a strong weekly pattern, and, if taken together, show that the relationship N(Q) is not a linear one. When Q is small, N grows like a second-order polynomial, while at large Q there is a tendency towards saturation, leading to an S-shaped relationship. Although visible in all data from all crashes, the data for the severe crashes display a less prominent saturation. As a by-product, the analysis performed here also demonstrates that the crash frequencies follow a negative binomial distribution, where both parameters of the distribution depend on the hour of the week, and, presumably, on the traffic state in this hour. The work presented in this paper aims at giving the reader a better understanding on how crash rates depend on exposure. View Full-Text
Keywords: road safety; traffic states; crash rates; temporal crash rate pattern road safety; traffic states; crash rates; temporal crash rate pattern
Show Figures

Figure 1

MDPI and ACS Style

Wagner, P.; Hoffmann, R.; Leich, A. Observations on the Relationship between Crash Frequency and Traffic Flow. Safety 2021, 7, 3. https://0-doi-org.brum.beds.ac.uk/10.3390/safety7010003

AMA Style

Wagner P, Hoffmann R, Leich A. Observations on the Relationship between Crash Frequency and Traffic Flow. Safety. 2021; 7(1):3. https://0-doi-org.brum.beds.ac.uk/10.3390/safety7010003

Chicago/Turabian Style

Wagner, Peter, Ragna Hoffmann, and Andreas Leich. 2021. "Observations on the Relationship between Crash Frequency and Traffic Flow" Safety 7, no. 1: 3. https://0-doi-org.brum.beds.ac.uk/10.3390/safety7010003

Find Other Styles
Note that from the first issue of 2016, MDPI journals use article numbers instead of page numbers. See further details here.

Article Access Map by Country/Region

1
Back to TopTop