Abstract

Bibliographic databases contain surrogates to a particular subset of the complete set of literature; some databases are very narrow in their scope, while others are multidisciplinary. These databases overlap in their coverage of the literature to a greater or lesser extent. The topic of Fuzzy Set Theory is examined to determine the overlap of coverage in the databases that index this topic. It was found that about 63% of records in the data set are unique to only one database, and the remaining 37% are duplicated in from two to 12 different databases. The overlap distribution is found to conform to a Lotka-type plot. The records with maximum overlap are identified; however, further work is needed to determine the significance of the high level of overlap in these records. The unique records are plotted using a Bradford-type form of data presentation and are found to conform (visually) to a hyperbolic distribution. The extent and causes of intra-database duplication (records duplicated in the one database) are also examined. Finally, the overlap in the top databases in the dataset were examined, and a high correlation was found between overlapping records, and overlapping DIALOG OneSearch categories.

Links and resources

Tags

community