Traffic&Transportation Journal
Sign In / Sign Up


Safety Impacts of the Actuated Signal Control at Urban Intersections
Sang Hyuk Lee, Daeseok Han
Keywords:semi-actuated signal controls, safety impacts, safety performance functions, EB approaches, urban intersections,


To reduce travel time, the actuated signal controls have been implemented at urban intersections. However, the safety impacts of actuated signal controls thus far have rarely been examined. In this assessment of the safety impact of urban intersections with semi-actuated signal controls, the safety performance functions and EB approaches were applied. The semi-actuated signal controls have increased injuries and total crashes in all crash types by around 5.9% and 3.8%, respectively. Regarding the most common crash types, such as angle, sideswipe & rear-end, and head-on crashes, semi-actuated signal controls have been seen to decrease injuries by 7.7%. Total crashes have been reduced by over 9.2% through the use of semi-actuated signal controls. This may be result of optimal signal timings considering traffic conditions during peak time periods. In conclusion, safety impact factors which have been established in this study can be used to improve safety and minimize travel times using semi-actuated signal controls.


Oh JT. Development of Severity Models for Vehicle Accident Injuries for Signalized Intersections in Rural Areas. KSCE J of Civil Engineering. 2006;10(3):219-225.

Young W, Archer J. Traffic Microsimulation Modeling to Study a Traffic Signal Incident Reduction Function. Transport Res Record. 2009;2103:80-87.

Li W, Tarko AP. Safety Consideration in Signal Coordination and Road Design on Urban Street. Presented at the 4th International Symposium on Highway Geometric Design; 2010.

Yun IS, Lee CK, Choi JH, Ko SJ. Safety Assessment of Signalized Intersection Using SSAM: A Case of Actuated Signal Control. J Korea Society of Intelligent Transportation System. 2011;10(6):1-14.

Kim Y, Huh JA. Development of an Actuated Traffic Signal Control Strategy to Minimize Dilemma Zone. J Korea Society of Intelligent Transportation System. 2002;1(1):58-69.

Lord D, Persaud BN. Accident Prediction Models With and Without Trend: Application of the Generalized Estimating Equations (GEE) Procedure. Presented at 79th Annual Meeting of the Transportation Research Board; 2000.

Ma J, Kockelman KM. Bayesian Multivariate Poisson Regression for Models of Injury Count, by Severity. Transport Res Record. 2006;1950:24-34.

Persaud BN, Palmisano J. Calibration and Transferability of Accident Prediction Models for Urban Intersections. Transport Res Record. 2002;1784:57-64.

Heydecker BG, Wu J. Identification of Sites for Road Accident Remedial Work by Bayesian Statistical Methods: An Example of Uncertain Inference. Advances in Engineering Software. 2001;32:859-869.

Miaou SP, Lord D. Modeling Traffic Crash-Flow Relationships for Intersections: Dispersion Parameter, Functional Form, and Bayes Versus Empirical Bayes. Presented at 82nd Annual Meeting of the Transportation Research Board; 2003.

Lord D, Washington SP, Ivan JN. Poisson, Poisson-Gamma and Zero-Inflated Regression Models of Motor Vehicle Crashes: Balancing Statistical fit and Theory. Accident Analysis Prevention. 2005;37:35-46.

Chin HC, Quddus MA. Applying the Random Effect Negative Binomial Model to Examine Traffic Accident Occurrence at Signalized Intersections. Accident Analysis Prevention. 2003;35(2):253-259.

Hauer E. Overdispersion in Modeling Accidents on Road Sections and in Empirical Bayes Estimation. Accident Analysis Prevention. 2001;33(6):799-808.

Li CS, Lu JC, Park JH, Kim K, Brinkley PA, Peterson JP. Multivariate Zero-Inflated Poisson Models and Their Applications. Technometrics. 1999;41(1):29-38.

Xi X, Saric Z, Kouhpanejade A. Freeway Incident Frequency Analysis Based on CART Method. Promet - Traffic & Transportation. 2014;26(3):191-199.

Jovanis PP, Chang H. Modeling the Relationship of Accidents to Miles Traveled. Transport Res Record. 2002;1068:42-51.

Li Z, Lee SH, Lee YD, Zhou B, Bamzai RA. Methodology for Assessing the Safety Impacts of Highway Shoulder Paving. Presented at T & DI Congress; 2010.

Carlin BP, Louis TA. Bayesian Methods for Data Analysis. CRC press, New York; 2009.

Greene WH. NLOGIT Version 3.0 User’s Manual. Econometric Software Inc., Bellport, NY; 2002.

Persaud B, Lyon C, Nguyen T. Empirical Bayes Procedure for Ranking Sites for Safety Investigation by Potential for Safety Improvement. Transport Res Record. 1999;1665:7-12.

Jeong SB, Hwang BH, Sung NM, Lee SH. Development of Evaluation Model for Black Spot Improvement Priorities by Using Empirical Bayes Method. J Korean Society of Transportation; 27(3):81-90.

Kwak YH. An Effect Analysis on the Improvement Strategies of Traffic Accident Area using Empirical Bayes Method. Master Degree Thesis, Hanyang University; 2006.

Bukljas Z, Culjak I, Zovak G. Using Traffic Conflict Method in Evaluating Traffic Safety at the Reconstructed Intersection, Promet - Traffic & Transportation. 2002;14(3):135-139.

Copyright (c) 2023 Sang Hyuk Lee, Daeseok Han

Published by
University of Zagreb, Faculty of Transport and Traffic Sciences
Online ISSN
Print ISSN
SCImago Journal & Country Rank
Publons logo
© Traffic&Transportation Journal