Document Type


Date of Award

Spring 5-31-1997

Degree Name

Master of Science in Computer Science - (M.S.)


Computer and Information Science

First Advisor

Jason T. L. Wang

Second Advisor

James A. McHugh

Third Advisor

Peter A. Ng


Change detection in structured documents (e.g. SGML is important in data warehousing, digital libraries and Internet databases. This thesis presents a graphical environment for detecting changes in the structured documents. We represent. each document by alp ordered labeled tree based on the underlying markup language. We then compare two documents by invoking previously developed algorithms for approximate pattern matching and pattern discovery in trees. Several operators are developed to support. the comparison of the documents; graphical devices are provided to facilitate the use of the operators. We believe the proposed tool is useful for not only document management, but also software maintenance, particularly configuration management and version control, where programs aro represented as parse trees and detecting changes in the trees provides a way to find the syntactic differences of two program versions.