tailieunhanh - Báo cáo khoa học: "Improving Search Results Quality by Customizing Summary Lengths"

Web search engines today typically show results as a list of titles and short snippets that summarize how the retrieved documents are related to the query. However, recent research suggests that longer summaries can be preferable for certain types of queries. This paper presents empirical evidence that judges can predict appropriate search result summary lengths, and that perceptions of search result quality can be affected by varying these result lengths. These findings have important implications for search results presentation, especially for natural language queries. . | Improving Search Results Quality by Customizing Summary Lengths Michael Kaisser University of Edinburgh 2 Buccleuch Place Edinburgh EH8 9LW Marti A. Hearst UC Berkeley 102 South Hall Berkeley CA 94705 hearst@ John B. Lowe Powerset Inc. 475 Brannan St. San Francisco CA 94107 johnblowe@ Abstract Web search engines today typically show results as a list of titles and short snippets that summarize how the retrieved documents are related to the query. However recent research suggests that longer summaries can be preferable for certain types of queries. This paper presents empirical evidence that judges can predict appropriate search result summary lengths and that perceptions of search result quality can be affected by varying these result lengths. These findings have important implications for search results presentation especially for natural language queries. 1 Introduction Search results listings on the web have become standardized as a list of information summarizing the retrieved documents. This summary information is often referred to as the document s surrogate Mar-chionini et al. 2008 . In older search systems such as those used in news and legal search the document surrogate typically consisted of the title and important metadata such as date author source and length of the article as well as the document s manually written abstract. In most cases the full text content of the document was not available to the search engine and so no extracts could be made. In web search document surrogates typically show the web page s title a URL and information extracted from the full text contents of the document. This latter part is referred to by several different names including summary abstract extract and snippet. Today it is standard for web search engines to show these summaries as one or two lines of text often with ellipses separating sentence fragments. However there is evidence that the ideal result length is .