Accession Number:

AD1005893

Title:

Automating Argument Construction

Descriptive Note:

Technical Report

Corporate Author:

SRI International Menlo Park United States

Personal Author(s):

Report Date:

1986-11-01

Pagination or Media Count:

21.0

Abstract:

Artificial Intelligence Center at SRI has been developing new technology to address the problem of automated information management within real-world contexts. The result of this work is a body of techniques for automated reasoning from evidence that we call evidential reasoning. The techniques are based upon the mathematics of belief functions developed by Dempster and Shafer and have been successfully applied to a variety of problems including intelligence analysis. We have developed both a formal basis and a framework for implementing automated reasoning systems based upon these techniques. Both the formal and practical approach can be divided into four parts 1 specifying a set of distinct propositional spaces, 2 specifying the interrelationships among these spaces, 3 representing bodies of evidence as belief distributions, and 4 establishing paths for the bodies of evidence to move through these spaces by means of evidential operations, eventually converging on spaces where the target questions can be answered. These steps specify a means for arguing from multiple bodies of evidence toward a particular probabilistic conclusion. Argument construction is the process by which such evidential analyses are constructed and is the analogue of constructing proof trees in a logical context. This technology features the ability to reason from uncertain, incomplete, and occasionally inaccurate information based upon seven evidential operations fusion, discounting, translating, projection, summarization, interpretation, and gisting. In implementing this formal approach, we have found that evidential arguments can be represented as graphs. To support the construction, modification, and interrogation of evidential arguments, we have developed Gister. Gister provides an interactive, menu-driven, graphical interface that allows these graphical structures to be easily manipulated.

Subject Categories:

  • Information Science
  • Linguistics
  • Operations Research
  • Cybernetics

Distribution Statement:

APPROVED FOR PUBLIC RELEASE