Solution techniques for location-allocation problems usually are not a part of micro-computer based geo-processing systems. The large volumes of data to process and store and the complexity of algorithms present a barrier to implementation of these solution techniques in a micro-computer environment. Yet decision-makers need analysis systems that return solutions to location selection problems in real time. We show that processing requirements for the most accurate heuristic, location-allocation algorithm can be drastically reduced by pre-processing inter-point distance data as both candidate and demand strings and exploiting the spatial structure of location-allocation problems by updating an allocation table. Consequently, solution times increase approximately linearly with problem size. These developments allow the solution of large problems (3,000 nodes) in a microcomputer-based, interactive decision-making environment. These methods are implemented in a micro-computer system and tests on three network problems validate our claims.

This is a report on the first meeting of the sixth NCGIA research initiative, entitled "Spatial Decision Support Systems." This meeting, held in Santa Barbara between March 14th and 18th, 1990, was attended by representatives of the NCGIA, university faculties from Canada, the UK and the US, government agencies in Canada and the US, and representatives of Canadian and US companies. The contents of this report are compiled from the notes of the organizers, materials prepared during the meeting and the personal notes of several of the participants.

NCGIA's Research Initiative 6 is concerned with the integration of geographic information systems and geographic information analysis to support problem-solving and decision-making. This Initiative was active from March 1990 until April 1993. This report describes the Center's research activities relating to the design and implementation of prototype systems that link geographic information systems and geographic information analysis. These included applications in retailing, marketing, socioeconomic modeling, and environmental modeling. The breadth of application areas is consistent with the pressing needs of environmental scientists and society in general to apply new spatial technologies to fundamental problems.

A bibliography of literature on spatial decision support systems compiled from sources including journal indices, book indices, and databases.

This is a report on the first meeting of the seventeenth NCGIA research initiative, entitled “Collaborative Spatial Decision-Making.” This meeting, held in Santa Barbara between September 16th and 19th, 1995, was attended by representatives of the NCGIA, university faculty members from North America and Europe, and representatives of US companies. The contents of this report are compiled from the notes of the organizers and student rapporteurs, materials prepared during the meeting and the personal notes of several of the participants.

This unit describes the concept, components and application of spatial decision support systems (SDSS). Using an example decision task—selecting a site for a retail store—it illustrates the nature of many spatial decision tasks as ill-defined or semi-structured and how SDSS can facilitate the decision-making process.