How accurate is the real-time traffic map information?
Engineers do their best to relate the traffic data collected at each intersection to a level of traffic congestion and color display on the map. In general, we have found through calibration efforts that the map is both reasonably accurate and consistent. Higher precision can be achieved over time through ongoing calibrations, field observation, user feedback and fine-tuning. Users should keep in mind, however, that these are estimates of congestion. Also, the rate of change of congestion is not displayed, and in some instances, could affect the map user. For instance, black could be displayed on a segment although the traffic or accident that resulted in black may be clearing rapidly. The map will inform the motorist of the black condition, but would not be able to inform the motorist that traffic is clearing and the segment may change to yellow shortly. Lastly, the vehicle detection loops described in question #7 may occasionally malfunction. When this occurs, black is displayed beca
