University of California Transportation Center

The research demonstrated innovative methods for using GPS-enhanced travel and activity monitoring to measure, analyze, and verify highly resolved travel patterns of low-income households for multiple modes and days. Previous studies suggest the travel of low-income households varies significantly from more affluent households, but our understanding of how low-income residents navigate the urban landscape throughout the day is limited since they are less likely to respond to travel surveys and, when they participate, are more likely to underreport travel. The Harbor Communities Time Location Study (HCTLS) addressed these limitations through targeted sampling and the integration of traditional activity/travel diary methods with portable GPS monitoring and follow-up prompted recall interviews to verify patterns revealed in simultaneous diary-GPS monitoring. In early 2008 we monitored 10-14 days of travel of 51 residents of Wilmington and western Long Beach, port-adjacent low-income communities impacted by high levels of congestion and pollution due to goods movement activities. Results provide valuable insights for transportation planners and policy makers into the travel modes and patterns of low-income households and the rate at which they seem to underreport travel and activities on travel/activity diaries.