Random Effect Models to Predict Operating Speed Distribution on Rural Two-Lane Highways
Publication: Journal of Transportation Engineering
Volume 142, Issue 6
Abstract
This paper presents the results obtained from the estimation of free-flow speed on two-lane rural highways. The data used for the analysis were collected in Northwest Italy using video cameras and a laser speed gun. The model structure adopted separates the estimate of the central tendency of speeds from the typical deviations of individual speeds. Hence, in the model, the same set of variables can be used to determine both the mean value and the standard deviation of the speed distribution; the desired speed percentile is then calculated by considering the associated standard normal random variable (). Random effects (RE) were included in the model to account for the variability in time and space of the data that contain multiple measurements for the same road/section/direction and to remove any dependency between estimation errors from individual observations.
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Acknowledgments
The research work included in this paper has been made possible thanks to the joint project between the Politecnico di Torino (Italy) and the University of Maryland (US) titled: “—Advanced Models, Methods and Materials for Sustainable, Safe and Smart Infrastructures.” The authors acknowledge funding received from the Compagnia di San Paolo (Italy) and from the Politecnico di Torino under the grant, “Bando per il Finanziamento di Progetti di Internazionalizzazione della Ricerca,” approved with the Rectoral Decree n. 208 of the 24th of May, 2013. The Città Metropolitana di Torino and the Provinces of Vercelli and Alessandria are greatly acknowledged for the access to the GIS databases used to collect roadway inventory information.
References
Bassani, M., Dalmazzo, D., Marinelli, G., and Cirillo, C. (2014). “The effects of road geometrics and traffic regulations on driver-preferred speeds in northern Italy. An exploratory analysis.” Transp. Res. Part F, 25, 10–26.
Bassani, M., and Mutani, G. (2012). “Effects of environmental lighting conditions on operating speeds on urban arterials.” Transp. Res. Rec., 2298, 78–87.
Bonneson, J. A. (2001). “Controls for horizontal curve design.” Transp. Res. Rec., 1751, 82–89.
Castro, M., Sánchez, J. F., Sánchez, J. A., and Iglesias, L. (2011). “Operating speed and speed differential for highway design consistency.” J. Transp. Eng., 837–840.
Figueroa Medina, A. M., and Tarko, A. P. (2005). “Speed factors on two-lane rural highways in free-flow conditions.” Transp. Res. Rec., 1912, 39–46.
Figueroa Medina, A. M., and Tarko, A. P. (2007). “Speed changes in the vicinity of horizontal curves on two-lane rural roads.” J. Transp. Eng., 215–222.
Hassan, Y. (2004). “Highway design consistency: Refining the state of knowledge and practice.” Transp. Res. Rec., 1881, 63–71.
Himes, S. C., Donnell, E. T., and Porter, R. J. (2011). “New insights on evaluations of design consistency for two-lane highways.” Transp. Res. Rec., 2262, 31–41.
Himes, S. C., Donnell, E. T., and Porter, R. J. (2013). “Posted speed limit: To include or not to include in operating speed models.” Transp. Res. Part A, 52, 23–33.
Lamm, R., and Choueiri, E. M. (1987). “Recommendations for evaluating horizontal design consistency based on investigations in the State of New York.” Transp. Res. Rec., 1122, 68–78.
Misaghi, P., and Hassan, Y. (2005). “Modeling operating speed and speed differential on two-lane rural roads.” J. Transp. Eng., 408–418.
NCHRP (National Cooperative Highway Research Program). (2003). “Design speed, operating speed, and posted speed practices.”, Transportation Research Board of the National Academies, Washington, DC.
R Development Core Team. (2005). “R: A language and environment for statistical computing.” 〈www.R-project.org〉 (Feb. 2, 2015).
Schwarz, G. (1978). “Estimating the dimension of a model.” Ann. Stat., 6(2), 461–464.
SETRA. (1986). “Vitesses pratiquées et geometric de la Route.”, Ministère de l’ Equipment, du Logement, de l’Aménagement du Territoire et des Transports, France (in French).
Transportation Research Circular. (2011). “Modeling operating speed.”, Transportation Research Board of the National Academies, Washington, DC.
Wang, J., Dixon, K. K., Li, H., and Hunter, M. (2006). “Operating speed model for low-speed urban tangent streets based on in-vehicle global positioning system data.” Transp. Res. Rec., 1961, 24–33.
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© 2016 American Society of Civil Engineers.
History
Received: Feb 19, 2015
Accepted: Dec 15, 2015
Published online: Feb 22, 2016
Published in print: Jun 1, 2016
Discussion open until: Jul 22, 2016
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