Publication Detail

Prototyping Experiments (I) to Study User Information Needs and Study of Preferences of Subjects for Alternative Display Formats


Research Report

Suggested Citation:
Chen, Wan-Hui, Paul P. Jovanis, Ryuichi Kitamura, Prasuna D. Reddy (1997) Prototyping Experiments (I) to Study User Information Needs and Study of Preferences of Subjects for Alternative Display Formats. Institute of Transportation Studies, University of California, Davis, Research Report UCD-ITS-RR-97-03

Pre-trip information systems have the potential to significantly impact the trip planning behavior of travelers. These systems promise to provide the user with a wide range of travel, mode and schedule options using a variety of interfaces. For the pre-trip information system to be effective and influential in impacting the trip planning behavior, it is necessary that the system provide 'useful information' which is communicated to the users in an 'effective manner'. The location and ease of access of the system, the range of services and the quality of information are all critical design issues which might affect the system usage and its influence on trip planning behavior.

The first objective of our research effort is to develop a detailed understanding of user needs and resulting functional requirements for a pre-trip planning system. In keeping with this objective a literature survey was performed, and based on this literature survey, a typology of information usage has been developed. This typology seeks to define the set of situations, constraints, users, and other variables that characterize the range of information uses, users, and travel scenarios, where pre-trip information systems could be utilized. This typology served as a preliminary basis for identifying information content required by the user. The information content requirements were then mapped on to suitable display formats appropriate for conveying these different information elements to the user. The capabilities of a variety of interfaces that could be utilized to convey the pre-trip information have been assessed in the light of the range of display formats that are permissible with these interfaces. The computer monitor is one of the most versatile interfaces since it allows a wide range of data display formats such as text, tables, maps, images, photographs, and audio output (with additional equipment).

The user information needs, and appropriate display formats have been integrated in designing a computerized menu-based pre-trip information system prototype. This information system prototype has been used as a tool for conducting prototyping experiments. The prototyping experiment enables us to accomplish most of the tasks for objectives 1 and 2 (namely to study user needs and functional requirements, and study subjects' preferences for alternative display formats, outlined in the proposal). A limited number of subjects were used for conducting the prototyping experiments. The subjects were required to use the system to make trip related decisions in three hypothetical travel scenarios of increasing complexity. As they used the system, open ended comments were elicited from the subjects. They were queried about the type of information they required for each of the scenarios as well as the various information elements that they felt were essential to make trip planning decisions. They were also requested to comment on the display formats and its effectiveness in conveying the information. The subjects were requested to make any comments or suggestions that would result in making the system more user-friendly and effective in conveying the pre-trip information. The following chapters describe the information system prototype, the experiment conducted, a summary of subjects' comments on information system, a summary of subjects' comments on system display formats, as well as a discussion of modifications made subsequent to the experiment based on subjects' comments.

The research effort performed thus far accomplishes most of the tasks corresponding to the project objectives one and two of the proposal and are in partial fulfillment of some of the tasks for objectives three and four outlined in the proposal.

The first objective involves the identification of user needs and functional requirements for pre-trip information systems. The development of an information typology along with the findings of the prototyping experiments have enabled us to accomplish most of the tasks (outlined in the proposal) associated with this objective. A telephone survey to study user perceptions and focus groups for testing the information usage typology have been canceled with the consent of PATH. The experiments have enabled us to complete the task of assessing the information needs for various types of travel decisions based on differences in the modes chosen. The last task of developing and testing conceptual models for pre-trip planning specific to travel context and modes will be accomplished by the second set of experiments that are about to be conducted shortly. These experiments will allow the study of information usage depending on trip type, user type, and travel context.

The second objective involves determining subjects' preferences and attitudes for alternative system formats. The task of assessing the capabilities of various media to convey pre-trip information has been fulfilled by comparing and assessing the capabilities of different interfaces in conveying different display formats. The interfaces pose a limitation of how the information is conveyed and compared. Different interfaces have also been compared based on the input interface- output interface compatibility and their ability to convey different types of information. Based on these studies, it has been determined that the computer monitor is a very versatile interface which allows a wide range of display formats, and is compatible with a wide range of input interfaces. A computerized menu based information system prototype has been developed using the computer monitor as an output interface and the mouse as an input interface. This system simulates a kiosk-type system with the touch screen as an input interface to a certain extent. The prototyping experiments have enabled the study of subjects' preferences and attitudes towards alternative system formats. So the major tasks outlined in the proposal for accomplishing this objective have been performed.

Currently work is underway to conduct the next set of experiments which, in addition to enabling the assessment of user preferences for different interfaces will also serve to provide further insight into user information needs and preferences for display formats.
The following chapters summarize the findings of the prototyping experiments.