Biomedical subjects

Wesley W Chu

Publications and source records attributed to Wesley W Chu.

3 recordsLinked to original sources

PubMed2003

IndexFinder: a method of extracting key concepts from clinical texts for indexing.

Extracting key concepts from clinical texts for indexing is an important task in implementing a medical digital library. Several methods are proposed for mapping free text into standard terms defined by the Unified Medical Language System (UMLS). For example, natural language processing techniques are used to map identified noun phrases into concepts. They are, however, not appropriate for real time applications. Therefore, in this paper, we present a new algorithm for generating all valid UMLS concepts by permuting the set of words in the input text and then filtering out the irrelevant concepts via syntactic and semantic filtering. We have implemented the algorithm as a web-based service that provides a search interface for researchers and computer programs. Our preliminary experiment shows that the algorithm is effective at discovering relevant UMLS concepts while achieving a throughput of 43K bytes of text per second. The tool can extract key concepts from clinical texts for indexing.

Abstracting and Indexing↗

PubMed2002

Modeling medical content for automated summarization.

Medical information is available from a variety of new online resources. Given the number and diversity of sources, methods must be found that will enable users to quickly assimilate and determine the content of a document. Summarization is one such tool that can help users to quickly determine the main points of a document. Previous methods to automatically summarize text documents typically do not attempt to infer or define the content of a document. Rather these systems rely on secondary features or clues that may point to content. This paper describes text summarization techniques that enable users to focus on the key content of a document. The techniques presented here analyze groups of similar documents in order to form a content model. The content model is used to select sentences forming the summary. The technique does not require additional knowledge sources; thus the method should be applicable to any set of text documents.

Automation↗

PubMed2002

Free-text medical document retrieval via phrase-based vector space model.

Many information retrieval systems are based on vector space model (VSM) that represents a document as a vector of index terms. Concepts have been proposed to replace word stems as the index terms to improve retrieval accuracy. However, past research revealed that such systems did not outperform the traditional stem-based systems. Incorporating conceptual similarity derived from knowledge sources should have the potential to improve retrieval accuracy. Yet the incompleteness of the knowledge source precludes significant improvement. To remedy this problem, we propose to represent documents using phrases. A phrase consists of multiple concepts and word stems. The similarity between two phrases is jointly determined by their conceptual similarity and their common word stems. The document similarity can in turn be derived from phrase similarities. Using OHSUMED as a test collection and UMLS as the knowledge source, our experiment results reveal that phrase-based VSM yields a 16% increase of retrieval accuracy compared to the stem-based model.

Abstracting and Indexing↗