Digital Library User Interface and Usability

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Digital Library User Interface and Usability

• Week 8

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Goals

• Discover elements of good interface design for
  digital libraries of various sorts
• Consider examples from DL usability evaluation as
  sources of insight.
• Look at the distinct requirements of interfaces
  to libraries of video and audio files

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Caveat

• Note --
• We have a whole class in User System Interface
• Everything in that class is relevant to User
  Interfaces for Digital Libraries
• One evening will not replace that course, nor
  will it capture all of the relevant factors.

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Note - to do later

• At the end of the class, I will ask you to do a
  reflection on the points raised. You will be
  asked to summarize the most important
  characteristics of a well-developed DL interface.
  
• As you continue your DL projects, be sure to
  apply the relevant components of these elements.

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The challenge

• A user interface for digital libraries must
  display large volumes of data effectively.
• Typically the user is presented with one or more
  overlapping windows that can be resized and
  rearranged.
• In digital libraries, a large amount of data
  spread through a number of resources necessitates
  intuitive interfaces for users to query and
  retrieve information.
• The ability to smoothly change the user's
  perspective from high-level summarization
  information down to a specific paragraph of a
  document or scene from a film remains a challenge
  to user interface researchers.

Source http//cimic.rutgers.edu/ieee_dltf.html
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Expectations of Digital Libraries

• Provide at least those services available in
  traditional libraries
• and more.
• A system is successful only to the degree to
  which the vast majority of its intended users are
  able to use its intended functionality

Hill 97
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User-centered design

• User-centered design for a digital library must
  include not only systems evaluation but also an
  understanding of the process of information
  seeking and use.
• Compared to a self-evident door handle -- once
  you see it, you know what it does and how to use
  it. No instruction is necessary.

Hill 97
8
Methods of evaluation

• Surveys
• Target user groups
• Focus groups from the intended audiences
• Ethnographic studies
• Audio/video taped sessions of users
• Analysis of feedback and comments
• Demographic analysis of beta tester registration
  data
• Log analysis
• We will consider in more detail next week as we
  look at quality measures

Hill 97
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Usability inspection of Digital Libraries

• To produce a product with high usability
• Client and user interviews
• Task analysis
• User class definitions
• Usage scenarios
• Iterative usability design
• Prototyping
• Design walk-throughs
• Usability evaluation

Unfortunately, most developers look at usability
analysis as something to do at the end of the
development process as a final test, rather than
as a part of the design process.
Source Hartson 04
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Evaluation

• Evaulation for any purpose has two major
  components
• Formative
• During development, spot check how things are
  progressing
• Identify problems that may prevent goals from
  being achieved
• Make adjustments to avoid the problems and get
  the project back on track
• Summative
• After development, see how well it all came out
• Lessons learned may be applicable to future
  projects, but are too late to affect the current
  one.
• Needed for reporting back to project sponsors on
  success of the work.

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Usability evaluation

• Lab-based formative evaluation
• Real and representative users
• Benchmark tasks
• Qualitative and quantitative data
• Leads to redesign where needed
• After deployment
• Real users doing real tasks in daily work
• Summative with respect to the deployed system
• Useful for later versions

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Usability inspection

• Lower cost option than full lab-based testing
• Applies to early designs, well-developed designs,
  and deployed systems
• Does not employ real users
• Expert based
• Usability engineering practitioners
• May be guided by typical user tasks
• Seeks to predict usability problems that users
  will encounter.

Hartson 04
13
Inspection categories

• User classes
• Know your user
• Example from the cited study
• Scientific researchers in computer science
• Administrators
• Do not use the regular interface, so not
  evaluated
• User tasks
• Search for technical reports on a set of criteria
• Browse the collection
• Register
• Submit
• Harvest

Hartson 04
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Search expanded

• Search options
• Simple search
• All bibliographic fields
• Group results by archive
• Sort
• Advanced search
• Focus on specific fields with filter options

Hartson 04
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Results - 1

• Submit and Harvest tasks not evaluated
• Specialized domain requirements
• Need evaluation with real users to do meaningful
  testing
• Report on Problems Found
• Usability problem types
• Wording, consistency
• Functionality
• Search and browse functionality
• Problem anything that impacts the users task
  performance or satisfaction.

Hartson 04
16
Categories of Problems

• General to most applications, GUIs
• Wording
• Consistency
• Graphic layout and organization
• Users model of the system

• Digital Library functionality
• Browsing
• Filtering
• Searching
• Document submission functions

Hartson 04
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Wording

• About 36 of the problems in the case
• Precise use of words in user interfaces is one
  of the most important design considerations for
  usability
• Clear, complete, correct
• Button and tab labels
• Menu choices
• Web links
• Crucial to help users learn and understand
  functionality
• Easiest problems to fix if someone with right
  skills is on the team.

Hartson 04
18
Search and Browse functionality

• Pretty basic to what a DL does!
• 18 of the problems were in that area.
• Designers consider these separate functions
• Users see them as extremely closely related
• Find the desired resource
• Should be designed together

Hartson 04
19
Usual Suspects

• Digital libraries prone to the same design faults
  as other interactive systems
• Consistency
• group and archive used interchangeably
• Different labels for the same concept used in
  different places
• Simple search on tab, Search all bibliographic
  field at function location
• Multiple terms referring to the same concept
  confuse users, slow learning
• Standardize terminology and check it carefully

Hartson 04
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Usual Suspects - 2

• Problems with Feedback
• Clearly indicate where the user is in the overall
  system
• Clicking a tab does not result in highlighting or
  any kind of feedback about which tab is the
  currently active choice.
• Selected institution (archive) highlighted when
  chosen, but not maintained after some other
  actions.

Hartson 04
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Usual suspects - 3

• Wording
• Use of jargon or slang, or unclear or missing
  labels
• Challenge for users
• Example in NCSTRL
• Several dates used. The labels for the dates do
  not clearly described what each represents.
• discovery date which is different from
  accession date
• Discovery date -- probably a developers term, and
  not likely to be of interest to the user.
• Use terms that are meaningful to users without
  explanation whenever possible. Resist presenting
  data that is not useful for user purposes.

Hartson 04
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Usual suspects - 4

• Wording, continued
• Example Submit to CoRR tab
• Could be Submit Technical Report(s) to CoRR
• Example Search all bibliographic fields
• Could be Simple Search Search all bibliograhic
  fields in selected archive (or for selected
  institution
• Other examples of unclear labels
• Archives Set - technical term from OAI-PMH
• DateStamp
• Discovery Date
• Label for the user, not the developer

Hartson 04
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Usual Suspects - 5

• Incorrect or inappropriate wording
• Search results label for browsing results
• hits (1-n) or total xxx hits displayed
• Not search results, just reports available for
  browsing
• Apparent use of combined code for browse and
  search.
• Label results appropriately, even scrupulously,
  for their real meaning.

Hartson 04
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Usual suspects - 6

• Appropriate terms
• Use of hits for individual search (or browse)
  results
• Commonly used
• Inappropriate slang, according to usability
  experts
• Considered unattractive, even slightly offensive
• Recommended something like Matches with search
  term
• Cosmetic consideration can have a positive affect
  on users impression of the site.

Hartson 04
25
Layout and design

• The whole point of a graphical user interface is
  to convey more information to the user in a short
  time.
• The GUI must support the user needs
• Example problems in the NCSTRL evaluation
• Menu choices - no logical order
• Reorganize by task or functionality
• Organize task interfaces by categories to present
  a structured system model and reduce cognitive
  workload.

Hartson 04
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Layout example

• Instead of randomly ordered tabs, group them by
• Information links
• About NCSTRL
• About CoRR
• OAI
• Help
• User tasks
• Simple search
• Advanced search
• Browse
• Register
• Submit technical reports to CoRR

Hartson 04
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Graphical design

• Proximity of elements suggests associations and
  relatedness
• Search button very close to OR radio box
• Applies equally to all parts of the dialog
• Consider the implications of placement and
  association of graphical elements.

Hartson 04
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Start off right

• Any application should have a home page that
  explains what the site is about and gives the
  user a sense of the overall site capability and
  use.
• NCSTRL starts with the Simple Search page, with
  no introduction.

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DL specific problems

• Searching, filtering, browsing
• User view all are aspects of finding a needed
  resource
• Developer view differences based on what must go
  in an index to support searching, how filtering
  is combined with searching to form a new query,
  etc.
• Usability suggestion combine search, browse,
  filter into one selection and navigation
  facility.
• Give users the power to combine these elements to
  serve their needs.

Hartson 04
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Iterative search

• Search is often implemented as a one-shot
  function.
• Users want to iterate on their query string to
  improve results
• NCSTRL does not show the query that produced the
  given results.
• Users want to prune the result set by applying a
  subsequent query to just those results
• Not available in NCSTRL
• Examples where it is available?

Hartson 04
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Browsing

• NCSTRL allows browsing only by institutions
  (archive)
• Other possibilities
• Date
• Author
• Subject
• Allow user activity that will serve user needs.
  Try to find out what users want before making
  decisions about services offered.

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Portal

• A portal ltisgt a single point of access to
  distributed systems that provides services to
  support user needs to search, browse, and
  contribute content, often linking to shared
  existing functionality at other sites.
• Portal pass through problem
• Does the portal add service, or just provide a
  link to a collection of other sites?

Hartson 04
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Portal - submission

• NCSTRL - submission to CoRR
• Link opens to another page, not directly offering
  the opportunity to submit.
• Disconnect for the user between the original page
  and the action promised.
• Link directly to the service offered without any
  intermediate pages unless needed in support of
  the service.

Hartson 04
34
Summary for NCSTRL case

• System exhibited many typical problems with user
  interfaces
• Investigation illuminated some issues specific to
  digital libraries or other systems for retrieving
  information.

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Another Case - CITIDEL
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CITIDEL

• Practical issue
• What would be the results of applying a usability
  review to CITIDEL, similar to that applied to
  NCSTRL?
• A few extra notes that come up in examining
  CITIDEL
• No way to submit a resource (only accepts
  metadata for resources located elsewhere)
• Is that an issue? Why or why not?
• Design of the front page
• Cluttered, confusing
• What is really essential? What is useful? How
  should it be organized?

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CITIDEL continued
www.citidel.org
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Video Digital Libraries

• Video digital libraries offer more challenges for
  interface design
• Information attributes are more complex
• Visual, audio, other media
• Indicators and controlling widgets
• Start, stop, reverse, jump to beginning/end, seek
  a particular frame or a frame with a specified
  characteristic

Source Lee 02
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Video Interface Features

• Video browsing
• Text description
• Transcript
• Single keyframe
• Storyboard
• Option re granularity of keyframe set
• Interactive hierarchical keyframe browser
• Keyframe slide show
• Video summary playing
• Playback
• Transcript playback synch
• Keyframe playback synch
• Text search playback and/or keyframe synch

• Cataloging
• Semi-automatic tool
• Manual tool
• Threshold adjustable before automatic
  segmentation
• Textual Query
• Natural language (or keyword)
• Category or keyword list browsing
• Audio information for indexing, browsing
• Intelligent frame selection

Source Lee 02
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Common features for Video DLs

• Most systems use a textual querying interface and
  few systems provide any form of visual query
  interface, probably indicating the need for
  further development in this area
• Most systems use keyframe(s) as their video
  browsing method
• Playback is provided in all listed systems,
  indicating that playback is regarded as a most
  important interface feature
• Whereas most systems provide more than one video
  browsing method (often transcript playback
  and/or keyframe playback), browsing aids such
  as synchronisation between different browsing
  methods are not often facilitated.

Source Lee 02
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Stages of Information seeking in Video Digital
Libraries

• Browsing and then selecting video programs (as a
  collection)
• Querying within a video program (content
  querying)
• Browsing the content of a video program
• Watching (part of) a video program
• Re-querying the video digital library and/or
  within a video program

Source Lee 02
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Summarizing stages of information seeking and the
interface elements that support them as described
in four researchers work.
Source Lee 02
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Granularity in Video Browsing

• Abstraction
• Reducing the information available to a
  manageable, usable subset
• Traditional video audio browsing
• One point of access
• Sequential
• Fast forward
• Difficult to see the content
• Need to return to the beginning to repeat search

Source Lee 02
44
Video Abstraction

• Levels to present (from Shneiderman 98)
• Overview first
• Zoom and Filter
• Details on Demand
• Example levels (from Christel 97)
• Title text format, very high level overview
• Poster frame single frame taken from the video
• Filmstrip a set of frames taken from the video
• Skim multiple significant bits of video
  sequences
• Time reference
• Significant in video
• Options include simple timeline, text
  specification of time of the current frame, depth
  of browsing unit

Source Lee 02
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Keyframe browsing

• Extract a set of frames from the video
• Display each as a still image
• Link each to play the video from that point
• Selection is not random
• Video analysis allows recognition
• Sudden change of camera shot
• Scenes with motion or largely stationary
• Video indexing based on frame-by-frame image
  comparison
• Similar to thumbnail browsing of image
  collections

Source Lee 02
46
Keyframe extraction for display on browsing
interface
Source Lee 02
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Keyframe extraction

• Manual
• Owner or editor explicitly selects the frames to
  be used as index elements
• Automatic
• Subsampling - select from regular intervals
• Easy, but may not be the best representation
• Automatic segmentation - break the video into
  meaningful chunks and sample each
• Shot boundary detection - note switch from one
  camera to another, or distinct events from one
  camera

Source Lee 02
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Displaying the frames

• Once the key frames are selected, display them
  for effective user interaction
• Storyboard
• Miniaturized keyframes in chronological order
• Aka keyframe list or filmstrip
• Slide show
• Keyframes displayed one at a time
• Hierarchically arranged
• Good when content is structured

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More detail

• For much more detail about Video browsing and
  presentation, see Lee 02.

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Summary

• Much of digital library user interface design and
  usability analysis is the same as that of other
  web services
• Keep the user central in the design phase
• Be careful about word use
• Organize the graphics and layout carefully
• Think about the user experience
• Some special considerations about DL usability
  have to do with DL services
• Search, filter, browse
• Connections with other collections to which this
  is a portal

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References

• Adam, N., Holowczak, R., Halem, M., Lal, N., and
  Yesha, Y. Digital Lbrary Technical Committee
  cimic.rutgers.edu/ieee_dltf.html
• Christel 97 Christel, M., Winkler, D. and
  Taylor, C. (1997) Multimedia abstractions for a
  digital video library Proceedings of the 2nd
  ACM International Conference on Digital Libraries
  (DL 97), Philadelphia, PA July, pp 21-29
• Hartson, H. R., Shivakmar, P, and Perez-Quiñones
  (2004) Usability inspection of digital
  libraries a case study International Joural of
  Digital Libraries 4 108-123
• Hill, L., Dolin, R., Frew, J., Kemp, R.,
  Larsgaard, M., Montello, D., Rae, M., and
  Simpson, J. user Evaluation Summary of the
  Metholologies and Results for the Alexandria
  Digital Library, University of California at
  Santa Barbara. www.asis.org/annual-97/alexia.htm
• Lee 02 Lee, H., and Smeaton, A. (2002)
  Designing the User Interface for the Físchlár
  Digital Video Library Journal of Digital
  Information, Volume 2, Issue 4 May 2002
  http//jodi.tamu.edu/Articles/v02/i04/Lee/2
• Shneiderman 98 Shneiderman, B (1998) Designing
  the user interface strategies for effective
  human-computer interaction, 3rd edition (Addison
  Wesley Longman)