Conclusion
This paper is an exploration of how an enormous and richly detailed set of GPS-based data might be transformed into a data- base to help transportation engineers and planners better under- stand driving behavior. It explains the challenges in converting geocoded data points into a meaningful database that describes the complexity of trips, routes, and tours of chained trips. And it investigates in detail the driving characteristics of a single driver over the course of a month to test how GPS data can be applied to better understand trip-making behavior. The main lesson from the study is that travel patterns are more complex than traditional travel surveys reveal. Although GPS data require substantial investments in data handling techniques, the database we developed offers several advantages over conventional travel survey data: travel routes between destinations are known; patterns can be observed in a single driver over a full 30 days; and events are captured as a driver is in motion, including speed, acceleration, turns, and sudden stops. The explorations carried out in this paper demonstrate the advantages of GPS data and suggest that the emerging technology will allow transportation engineers and planners to measure more precisely than in previous studies the effect of driving on such urgent issues as pollution emissions and energy consumption.