CS/INFO 430 Information Retrieval

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CS/INFO 430Information Retrieval
Lecture 23 Usability 1
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Course Administration
Assignment 4 Due Friday, December
1 Extensions only for exceptional circumstances
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Usability Lectures
Usability 1 Browsing and search
interfaces Usability 2 Evaluation with human in
the loop Usability 3 Usability design
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Browsing The Human in the Loop
Return objects
Return hits
Browse documents
Search index
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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
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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
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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
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Browse Catalog Record
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Hierarchical browsing
Level 0
Level 1
Level 2
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Hierarchical browsing collections
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Alphabetical browsing http//nsdl.org/
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Alphabetical browsing subject headings
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Browsing the Content of Indexes
Show the users the terms that occur in indexes,
such as subject headings. Example Library of
CongressAmerican Memory http//memory.loc.gov/
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Subject headings used in index
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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/
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Browse everything
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Filter "New York"
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Sort "date"
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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
• Heuristic Evaluation
• ... Jacob Nielsen's Online Writings on Heuristic
  Evaluation. 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

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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
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Dynamic Return Hits
Dynamic snippets
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Precomputed Return Hits
Pre-computed snippets
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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/fol
iocgi.exe/...
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Dynamic Snippets
Legal Information Institute www2.law.cornell.edu/.
../doc/7B_at_17D/ hit_headings/words4/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/7Bt262627D/ pageitems7Bbody7D/hit_headin
gs/words4 - 13k - Cached -Similar pages
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Pre-computed Snippets
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Dynamic Snippets with Pre-computed Summary
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Dynamic Snippets with Pre-computed Summary
Pre-computer summary, with space for dynamic
snippet
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Dynamic Snippets with Pre-computed Summary
Complete record with dynamic snippet
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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

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Google

• Spacious organization

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AltaVista

• Division of functionality to different pages

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ACM Digital Library
Emphasized components
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ACM Digital Library advance search
Different ways to insert query
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Yahoo!
Cramped organization
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The Old Yahoo! Interface
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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.ya
hoo.com/
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