How Road Sage Forecasts Future Travel Times:

As many experienced drivers know, traffic jams tend to reappear in the same places and at the same times. On the other hand, traffic can be as unpredictable as weather. Our system collects speed data from Caltrans detectors installed within the pavement of Bay Area freeways; we average it out over long periods of time to see where the most frequent bottlenecks are, and where the more spurious slowdowns are likely to happen. Based on these numbers, we estimate freeway speeds and route travel times for every day and every hour of the week. In this way, we provide our users with a tool that allows them to anticipate traffic bottlenecks and to make their travel plans in accordance with the predicted road conditions.