Estimation for Seasonal Factors of Similarity-Based Traffic for Urban Roads in Florida

The Florida Department of Transportation (FDOT) estimates seasonal factors (SFs) by using data obtained from approximately 300 telemetry traffic monitoring sites, which are used in the calculation of annual average daily traffic (AADT) at portable traffic monitoring sites (PTMSs). Both the estimation and the application of seasonal factors are based on the consideration of similarities in the traffic characteristics of roads and on engineering judgment. FDOT desires a more objective and data-driven method to improve the accuracy of SF estimation for PTMSs. A previous study investigated traffic and land use data in Southeast and North Florida and demonstrated the possibility of identifying the link between land use variables and seasonal factors. This paper describes a statewide investigation to identify potentially influential variables that contribute to seasonal fluctuations in traffic volumes in urban areas in Florida. A method is also developed for assigning seasonal factors to PTMSs. The test results show that the errors of the estimated seasonal factors are on average 5%. This method is promising for application in both urban and rural areas to improve accuracy in AADT estimation.