Michael G. McNally

A model of activity participation and travel interactions between household heads

A structural model is used to explain activity interactions between heads of households, and, in so doing, to explain household demand for travel. The model attempts to capture links between activity participation and associated derived travel, links between activities performed by male and female heads, links between types of travel, and time-budget feedbacks from travel to activity participation. Data for pairs of opposite gender heads of households are from the 1994 Portland Activity and Travel Survey. The results suggest that a feedback mechanism should be introduced in trip generation models to reflect the effect of activity frequency and duration on the level of associated travel.

A model of complex travel behavior: Part I—Theoretical development

This paper presents a policy sensitive approach to modeling travel behavior based on activity pattern analysis. A theoretical model of complex travel behavior is formulated on a recognition of a wide range of interdependencies associated with an individuals travel decisions in a constrained environment. Travel is viewed as input to a more basic process involving activity decisions. A fundamental tenet of this approach is that travel decisions are driven by the collection of activities that form an agenda for participation; the utility of any specific travel decision can be determined only within the context of the entire agenda. Based on the theoretical model of complex travel behavior, an operational system of models, STARCHILD (Simulation of Travel/Activity Responses to Complex Household Interactive Logistic Decisions), has been developed to examine the formation of household travel/activity patterns, and is presented in a companion paper (Recker et al, 1985).

A model of complex travel behavior: Part II—An operational model

Abstract Based on the theoretical model of complex travel behavior developed in a companion paper (Recker et al. , 1986), an operational system of models, STARCHILD (Simulation of Travel/Activity Responses to Complex Household Interactive Logistic Decisions), has been developed to examine the formation of household travel/activity patterns. The system employs a simulation approach in combination with techniques of pattern recognition, multiobjective optimization and disaggregate choice models. Initial empirical verification of the system of models is presented based on results obtained from a sample data set.

ASSESSMENT OF INFLUENCE OF LAND USE-TRANSPORTATION SYSTEM ON TRAVEL BEHAVIOR

An empirical assessment of the interaction between the land use–transportation system and travel behavior is presented. A methodology for identifying a range of land use–transportation systems by a clustering technique with network and land use inputs was developed. Twenty neighborhoods from Orange County, California, were considered in this process. Three groups, or themes, were found to best represent the neighborhoods in the sample area: one each associated with the conventional definition of traditional and neotraditional neighborhood design (TND) and planned unit development (PUD) neighborhoods and one representing neighborhoods that blend characteristics of TND and PUD. Conventional measures of individual travel behavior were compared with an analysis of variance between the themes to identify significant differences, controlling for socioeconomic characteristics. Research results include the development of (a) a systematic methodology to identify a more explicit land use–transportation dimension, (b) an estimate of the potential effectiveness of design-oriented solutions to reduce automobile congestion by using the developed themes, and (c) a preliminary assessment of the extent to which development themes can be used to improve the current modeling framework.

A conflict model and interactive simulator (FASTCARS) for predicting enroute driver behavior in response to real-time traffic condition information

This paper proposes a theoretical methodology and practical data collection approach for modeling enroute driver behavioral choice under Advanced Traveler Information Systems (ATIS). The theoretical framework is based on conflict assessment and resolution theories popularized in psychology and applied to models of individual consumer behavior. It is posed that enroute assessment and adjustment is a reactionary process influenced by increased conflict arousal and motivation to change. When conflict rises to a level at which conflict exceeds a personal threshold of tolerance, drivers are likely to alter enroute behavior to alleviate conflict through either route diversion of goal revision. Assessment and response to conflict arousal directly relate to the drivers abilities to perceive and predict network conditions in conjunction with familiarity of network configurations and accessible alternate routes.Data collection is accomplished through FASTCARS (Freeway andArterialStreetTrafficConflictArousal andResolutionSimulator), in interactive microcomputer-based driving simulator. Limited real-world implementation of ATIS has made it difficult to study or predict individual driver reaction to these technologies. It is contended here that in-laboratory experimentation with interactive route choice simulators can substitute for the lack of real-world applications and provide an alternate approach to data collection and driver behavior analysis. This paper will explain how FASTCARS is useful for collecting data and testing theories of driver behavior.

On the structure of weekly activity/travel patterns

Understanding the process of activity scheduling is a critical prerequisite to an understanding changes in travel behavior. To examine this process, a web-based activity survey program, REACT!, was developed to collect household activity scheduling data. REACT! is unique in that it records the evolution of activity schedules from intentions to final outcomes for a multi-day period. This paper summarizes an investigation of the structure of activity/travel patterns based on a REACT! data set from a pilot study conducted in Irvine, California. The term structure refers to the outcome of a set of decisions facing individuals as they conduct their daily activities. At a minimum, structure can be interpreted as the sequence by which various activities enter ones daily activity scheduling process. Results of the empirical analyses show that activities of shorter duration were more likely to be opportunistically inserted in a schedule already anchored by longer duration counterparts. Additionally, analysis of tour structure reveals that many trip-chains were formed opportunistically. Travel time required to reach an activity was also positively related to the scheduling horizon for the activity, with more distant stops being planned earlier than closer locations.

Travel/activity analysis: Pattern recognition, classification and interpretation

This paper presents a methodology for the analysis of travel/activity patterns based on a classification procedure in which the set of measurements that define human movement is represented by a pattern vector. Transformation techniques are then applied to the pattern vectors to develop a taxonomy for the pattern space. Subsequent inversion of the transformed patterns yields representative activity patterns that can be related to socioeconomic and urban form characteristics. Pattern recognition theory is demonstrated to be an effective means by which complex travel/activity patterns can be transformed into a structurally simpler space for purposes of planning and analysis.

In-Laboratory Experiments to Investigate Driver Behavior under Advanced Traveler Information Systems (ATIS)

In-laboratory experimentation with interactive microcomputer simulation is a useful tool for studying the dynamics of driver behavior in response to advanced traveler information systems. Limited real-world implementation of these information systems has made it difficult to observe and study how drivers seek, acquire, process, and respond to real-time information. This paper describes the design and preliminary testing of an interactive microcomputer-based animated simulator, developed at the University of California, Irvine, to model pre-trip and enroute driver travel choices in the presence of advanced traveler information systems. The advantages of this simulator are realized in its versatility to model driver decision processing while presenting a realistic representation of the travel choice domain. Results from a case study revealed that increased driver familiarity with travel conditions and network layout reduces driver reliance on information systems and influences drivers diversion behavior.

EXPERIMENTS WITH COMPUTERIZED SELF-ADMINISTRATIVE ACTIVITY SURVEY

The process of activity scheduling is crucial to the understanding of travel behavior changes. In-depth research is urgently needed to unearth this process. A new computer program, REACT!, was developed to collect household activity scheduling data for this purpose. The program is implemented as a stand-alone program with Internet connectivity for remote data transmission. It also contains a geographic information system for location identification and a special feature that traces the decisions in the scheduling process. A pilot study was conducted in Irvine, California, to evaluate the program’s performance. Preliminary analysis validated the program’s capability of guiding participants to complete data entry tasks on their own; thus, the objective of reducing the cost of human resources for such a computerized survey is achieved. Other positive results were obtained regarding the objectives of reducing instrumental biases and expanding program capabilities. Areas for improvement were identified in the pilot study. On the basis of the findings, REACT! represents an ideal platform for a computerized household survey that can produce data for activity-based travel models.

Measuring the impact of efficient household travel decisions on potential travel time savings and accessibility gains

Using the conceptual framework of time-space geography, this paper incorporates both spatio-temporal constraints and household interaction effects into a meaningful measure of the potential of a household to interact with the built environment. Within this context, personal accessibility is described as a measure of the potential ability of individuals within a household not only to reach activity opportunities but to do so with sufficient time available for participation in those activities, subject to the spatio-temporal constraints imposed by their daily obligations and transportation supply environment. The incorporation of activity-based concepts in the measurement of accessibility as a product of travel time savings not only explicitly acknowledges a temporal dimension in assessing the potential for spatial interaction but also expands the applicability of accessibility consideration to such real-world policy options as the promotion of ride-sharing and trip chaining behaviors. An empirical application of the model system provides an indication of the potential of activity-based modeling approaches to assess the bounds on achievable improvements in accessibility and travel time based on daily household activity patterns. It also provides an assessment of roles for trip chaining and ride-sharing as potentially effective methods to facilitate transportation policy objectives.