This research is concerned with the modeling and manipulation of uncertain and inaccurate information in database systems. Database systems are evolving into knowledge-base systems, and are increasingly used in applications where handling uncertain and inaccurate data is essential. The research objectives include: (1) Extending existing methods for the modeling and management of uncertain and inaccurate data to contemporary database models such as object-oriented databases, (2) investigating techniques of combining information obtained from different sources and characterizing the application domains suitable for each technique, (3) devising methods to estimate and update credibility of information sources, and (4) applying these techniques to the extraction of useful information from large volumes of data. The results of this research can be used in realizing more intelligent database and knowledge-base systems that are suitable for applications that require handling uncertain and inaccurate information such as medical, legal and military applications.
