Mobile, location-aware devices raise the potential for fundamentally new information services. However, this potential has not been realized. This is due in part to the absence of a firm conceptual and empirical foundation. This proposal explores one basis for constructing the requisite foundation: socially defined places. How places (such as schools, offices, or theaters) shape behavior has been explored in environmental psychology and architecture, but the notion of 'place' has not been operationalized for use in interactive systems. This project takes on that task. The key hypotheses are that (a) people's information and communication needs are relative to place types, and (b) making 'place' a first-class computational object will increase the effectiveness and usability of location-based systems. This project will test the hypotheses through a combination of ethnographic studies, development of novel algorithms and interfaces, and laboratory and field studies, leading to the following results: 1) additional empirical knowledge about the concept of place and its role in organizing people's activities; 2) a conceptual framework and guidelines useful to designers of location-based systems; 3) a general infrastructure for place-centered community information sharing systems; and 4) field studies and laboratory evaluations that demonstrate the utility and acceptability of such systems.
