Textual Similarity: Comparing texts in order to discover how closely they discuss the same topics

This thesis describes the design and implementation of a tool for measuring textual similarity. The thesis looks into different aspects of text processing and graph searching in an attempt to define similarity. Furthermore, a solution for measuring textual similarity is proposed and implemented. Challenges such as disambiguation of word senses, part-of-speech tagging and several graph searching algorithms are described and used in the measurements. The developed tool is tested using human evaluation of textual similarity and it is concluded that the tool to some degree is able to measure textual similarity with the same results as a human being.