The primary goal of activity-based models is a fundamental examination of the behavioral process that results in revealed travel behavior. To reveal this process, a new computer program, iCHASE, has been developed to collect data for a study of the determinants of travel and activity behavior in households. These data are inherently dynamic, since respondents record planned activity schedules and then update these schedules on a daily basis, fully defined in time and space. The resultant data will facilitate the identification of fundamental inter-relationships among a comprehensive range of revealed travel and activity participation variables, leading toward the identification of the critical variables, relationships and rules that govern that behavior. It is believed that an Internet-based travel survey, particularly one as rich in resultant content as iCHASE, will significantly reduce data collection costs, improve data quality and quantity and allow for continuous data collection.

The primary goal of activity-based models is a fundamental examination of the behavioral process that results in revealed travel behavior. To reveal this process, a new computer program, REACT!1, has been developed to collect data for a study of the determinants of travel and activity behavior in households. This data is inherently dynamic, since respondents record planned activity schedules and then update these schedules, on a daily basis, fully defined in time and space. The resultant data will facilitate the identification of fundamental inter-relationship among a comprehensive range of revealed travel and activity participation variables, leading toward the identification of what are the critical variables, relationships, and rules that govern that behavior. It is believed that an internet-based travel survey, particularly one as rich in resultant content as REACT!, will significantly reduce data collection costs, improve data quality and quantity, and allow for continuous data collection. The purpose of this paper is to describe features of REACT! and to present preliminary results from a pilot study.

The primary goal of activity-based models is a fundamental examination of the behavioral processes that results in revealed travel behavior. To reveal this process, a new computer program, REACT!, has been developed to collect data for a study of the determinants of travel and activity behavior in households. These data are inherently dynamic, since respondents record planned activity schedules and them update these schedules on a daily basis, fully defined in time and space. The resultant data will facilitate the identification of fundamental inter-relationships among a comprehensive range of revealed travel and activity participation variables, leading toward the identification of the critical variables, relationships and rules that govern that behavior. It is believed that an internet-based travel survey, particularly one as rich in resultant content as REACT!, will significantly reduce data collection costgs, improve data quality and quantity, and allow for continuous data collection. The purpose of this paper is to describe features of REACT! and to present preliminary results from a pilot study.

The rapid advancement of technology has created the opportunity for applying new, powerful tools to transportation engineering problems, but often the very speed of technological change hinders the adoption of these tools in a research environment. This paper documents the development of an extensible data collection unit (EDCU). The unit combines a standard GPS unit, a cellular data modem, and an embedded processor running the Linux operating system. Some preliminary uses and applications of the EDCU are presented as well. The EDCU satisfies multiple functional requirements, due to the flexibility of its modular components and its full-powered operating system. The EDCU will serve the in-vehicle data collection needs of travel demand modelers and ITS researchers for the forseeable future.