1	Digital Libraries Usability of OPACs and retrieval engines* Week 9 KAN Min-Yen * Mostly based on Hearst’s Chapter in Modern Information Retrieval
2	What is HCI? For digital libraries, it is the means of expediting the information seeking process for a human user “When an interactive system is well-designed, the interface almost disappears, enabling users to concentrate on their work, exploration and pleasure” --- Shneiderman 97
3	Tenets of HCI Offer informative feedback Reduce working memory load Provide alternative interfaces for novice and expert users Methods: Color and Highlighting Pan / Zoom Focus + Context Overview + Details
4	Evaluating HCI Ergonomics (human factors) time to learn speed of performance rate of errors retention over time subjective satisfaction
5	ISP Overview
6	Outline Searching Query formulation Displaying results Browsing Categories and Hierarchies Integrating Frameworks
7	Query specification Old: originated from command line interfaces Suit the system, not the user e.g. “FIND TW Mt St. Helens AND DATE 1981” Then: translated for users on OPACs Subject: Date: 1980 – 1985 1986-1990 Now: graphical means for query specification
8	VQuery (Jones 98)
9	Filter / Flow model Users can select from the set of attributes and get an appropriate filter widget (type-in for interest areas, sliders for cost, and buttons for scholarships) The widget is placed on the screen with flow lines showing ANDs (sequential flow) and ORs (parallel flows). Water flow dynamically indicates relevant # of items
10	Against a controlled vocabulary Lists Seen on last slide from Filter / Flow Only good if limited number of entries Partial Fill-in Show possible completions of query terms if under a certain number (~ 5) Re-writing of form fill-in queries Who is the leader of Sudan? à Who is the head of state of X (Sudan)?
11	Tiles (Anick et al. 90) Use table to represent conjunction and disjunction Conjunction (AND): rows Disjunction: columns Use activation to see query preview from index
12	Query by Example
13	Faceted Metadata Faceted objects give rise to easy methods for summarizing the data The Flamenco Project http://flamenco.sims.berkeley.edu/cgi-bin/flamenco/arts/Flamenco?username=default Facet Map http://facetmap.com
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15	Geographic queries Geospatial data makes the 2 & 3-D visualization a good metaphor
16	Geospatial queries Point-in-polygon Region Distance and Buffer Zone Path Multimedia
17	Results display and integration
18	Keyword in Context (KWIC)
19	Tilebars (Hearst 95) Each row represents a topic (conjunction) The darkness of each tile in a row represent the frequency of occurrence of an item
20	Infocrystal (Spoerri 95) Explosion of the Venn Diagram Uses shape and color to model to organize results
21	More on Infocrystal
22	Superbook Searching a software technical manual Use a expandable table of contents to show results Shows hits within each level as query preview Closely modeled by browser in Windows Explorer 12 An Interactive Environment 10 Preface 1 How to Beat the Lottery 1 Tutorial Introduction to 7 Graphical Methods in S 2 Loading in Data … 3 Building Plots 2 Specialized Plots 2 Advanced Use of S 2 Appendix I
23	Cha-cha Brings this paradigm to website searching
24	Tablelens (InXight) http://www.tablelens.com Focus + context to give fisheye distortion to table rows and values
25	Cartographic Representations
26	Scatter / Gather
27	Scatter / Gather
28	Visualizing Hierarchies Fisheye zoom (Furnas 84) One implementation: Inxight’s StarTree http://www.inxight.com/ VizServerDemos/demo/ nasa/index.html
29	Summarization atop IR Like Superbook, but trades focus for extractive summary (Kan et al. 02) Relevant: information for summary Irrelevant: too broad or not on topic, for broader queries Intricate: too detailed, for follow-ups
30	Merging Document Topic Trees Norm for a particular type of document (e.g. travel leaflets, Univ. department descriptions) Create by aligning topics in trees by similarity
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32	Additional notes on faceted interface Multiple interfaces possible Columnar style Drop down list style Indented ancestors
33	Multiviews via Magic Lenses More than two views of the same space Lenses show and hide information that isn’t pertinent Has been applied in query focusing as well Demo: http://www.memorialhall.mass.edu/activities/media.jsp?itemid=15414&img=0
34	Bibliometric citations
35	With citation rates
36	Zoom in on the artery
37	Relevance feedback Koenenmann and Belkin (96) checked whether relevance feedback helped users Control: no RF Opaque: saw new documents Transparent: can see modifications Penetrable: can see modifications and change them Best one Possible conclusion: RF can help users create better queries as a form of online training
38	Query History Relevance feedback as one form Pros: Saved searches can help tune a generic system Decide whether to use advance or naïve interface for person Start off where one left off Cons: Need to track the user What happens if multiple purposes or used for guests? (e.g. Buying gifts for a friend)
39	Conclusions New systems show advanced text and graphics / animated displays but many are not yet well-evaluated Tighter integration in query and display Simultaneous browsing and searching support at all levels Screen real estate proportions in frameworks dictate useful alternatives
40	To think about What types of information do these various UI need to calculate at run-time and what types can be pre-computed? How do these UI support the tenets we mentioned at the beginning? Do you feel that HTML / WWW has enhanced UI design or deterred its creativity? For images and audio: When is query by example a useful technique and when is it inferior to a search using metadata?