Benchmarking travel time estimates

Travel time estimates are widely regarded as the most practical information about traffic conditions available to individual drivers. Although there are numerous data collection and estimation methods in use today, few attempts have been made to evaluate them in a systematic manner. Even more fundamentally, there are no broadly accepted metrics to measure the quality of travel time estimates. The study exposes the methodology and tools employed to conduct a benchmark of travel time estimates in the San Francisco Bay Area. The methodology and the proposed quality measures are intended to set a standard that can be universally applied. Their use is illustrated through a sample data set collected for 24 h on one Bay Area freeway.