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Learn about the importance of usability in browsing and search interfaces, including topics such as starting points, effective feedback, convenience, browsing methods, filtering and sorting, snippets, and design considerations.
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CS/INFO 430Information Retrieval Lecture 23 Usability 1
Course Administration Assignment 4 • Due Friday, December 1 • Extensions only for exceptional circumstances
Usability Lectures Usability 1: Browsing and search interfaces Usability 2: Evaluation with human in the loop Usability 3: Usability design
Browsing: The Human in the Loop Return objects Return hits Browse documents Search index
Web Search: Browsing Users give queries of 2 to 4 words Most users click only on the first few results; few go beyond the fold on the first page 80% of users, use search engine to find sites search to find site browse to find information Amil Singhal, Google, 2004
Browsing in Information Space Starting point x x x x x x x x x x x x x x Effectiveness depends on (a) Starting point (b) Effective feedback (c) Convenience
Convenience when Browsing If documents are accessible online, user can browse content. • Can compensate for weaknesses in the underlying search system, e.g., the difficulty of indexing Web documents • Requires rapid delivery to the desktop Otherwise, the user can browse substitutes, e.g., catalog records, subject hierarchies, etc. • Puts heavy demands on the precision/recall of the underlying search system
Hierarchical browsing Level 0 Level 1 Level 2
Alphabetical browsing http://nsdl.org/
Browsing the Content of Indexes Show the users the terms that occur in indexes, such as subject headings. Example: Library of Congress:American Memory http://memory.loc.gov/
Browsing by Filtering and Sorting Filters allow users to reject categories of information. Sorting by various criteria allows users to organize information for rapid scanning Example: Research Libraries Group Cultural Materials http://cmi.rlg.org/
Snippets • A snippet is a short record that a search system returns to describe and link to a hit. • Example: Web search “Nielsen evaluation heuristics” HeuristicEvaluation ... Jacob Nielsen's Online Writings on HeuristicEvaluation. How to conduct a heuristic evaluation; A list of ten recommended heuristics for usable interface design ...www.useit.com/papers/heuristic/ - 5k - Cached - Similar pages
Usability of Search: Snippets Choices in designing snippets: • Dynamic (generated from query + document) or pre-computed (from document only) • Content only or with related information (e.g., subject hierarchies) • Highlighting of search terms • Length of snippet v. number on page User must understand why the hit was returned
Dynamic Return Hits Dynamic snippets
Precomputed Return Hits Pre-computed snippets
Pre-computed Snippets In general dynamic snippets are superior because they fit the user's expectations, but they can fail badly. Example: Web search "brown topeka kansas" Legal Information Institute Brown v. Board of Education, 347 U.S. 483 (1954) (USSC+) 1. Syllabus , 2. Full Decision , 3. Syllabus & Opinions Only... www2.law.cornell.edu/cgi-bin/foliocgi.exe/...
Dynamic Snippets Legal Information Institutewww2.law.cornell.edu/.../doc/%7B@1%7D/ hit_headings/words=4/hits_only - 2k - Oct 27, 2003 - Cached -Similar pages DOC BodyPage ... Case Information. Brown v. Board of Education of Topeka . No. 1. ... APPEAL FROM THE UNITED STATES DISTRICT COURT FOR THE DISTRICT OF KANSAS [*]. Syllabus. ...www2.law.cornell.edu/.../doc/%7Bt26262%7D/ pageitems=%7Bbody%7D/hit_headings/words=4 - 13k - Cached -Similar pages
Dynamic Snippets with Pre-computed Summary Pre-computer summary, with space for dynamic snippet
Dynamic Snippets with Pre-computed Summary Complete record with dynamic snippet
Designing the Search PageMaking Decisions • Overall organization: • Spacious or cramped • Division of functionality to different pages • Positioning components in the interface • Emphasizing parts of the interface • Query insertion: insert text string or fill in text boxes • Interactivity of search results • Performance requirements
Google Spacious organization
AltaVista Division of functionality to different pages
ACM Digital Library Emphasized components
ACM Digital Library advance search Different ways to insert query
Yahoo! Cramped organization
The Yahoo! Interface The Yahoo interface is cluttered and unattractive, yet Yahoo is one of the most successful of all web sites. Why is this interface successful? • Very many branches from a single web page saves the need for hierarchy of menus. • Simple html markup ensures that the page renders quickly and accurately on all browsers. • Slow changes over the years means that users are familiar with it. http://www.yahoo.com/