Collection, Screening, and Evaluation of Vehicle Occupancy Data

In 2008, the Georgia State Road and Tollway Authority and the Georgia Department of Transportation successfully applied to the U.S. Department of Transportation for seed funding under the Congestion Reduction Demonstration Program Grant to convert the congested I-85 high-occupancyvehicle (HOV) lane to a high-occupancy-toll (HOT) lane. The facility was converted into a HOT lane and opened on October 1, 2011. This paper reports on the collection, processing, and filtering of the vehicle occupancy data and the factors that influenced vehicle occupancy along the I-85 corridor both before and after the conversion. The research effort used regression tree analysis techniques to identify data collector bias and then the effects of different factors such as season, data collection site, morning peak-evening peak, and lane type on vehicle occupancy. The study found that vehicle occupancy data on Monday were different from those data collected on Tuesdays, Wednesdays, and Thursdays. The study identified data collec...