Information Retrieval:
Human-Computer Interfaces
and Information Access Process
Introduction
Information seeking is an imprecise
process.
– Users have fuzzy understanding of how to
achieve their goals
– Users select among sources, formulate their
queries, review search results, …
IR interfaces need to support this process
Differences in IR retrieval quality can be
dwarfed by differences in interface quality
An Information Task
User explicitly or implicitly expresses
information need to system
System locates information based on
expression of need
System presents information to user
User interacts with information to solve
task
Human-Computer Interaction
What makes an effective human-computer interface?
“Well designed, effective computer systems generate
positive feelings of success, competence, mastery,
and clarity in the user community.
When an interactive system is well-designed, the
interface almost disappears, enabling users to
concentrate on their work, exploration, or pleasure.”
(Ben Shneiderman)
One Set of Design Principles
HCI includes a number of lists of design
principles (rules of thumb for good design)
Selecting list and principles is personal choice
and context dependent.
Shneiderman’s set includes:
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feedback
reversal of actions
Internal locus of control
reduce working memory load
alternative interfaces for novice and expert users
Offer Informative Feedback
Comes from early HCI models viewing user
interaction as a two-way communication
between user and system.
Information retrieval includes feedback on
– relationship between query and documents
retrieved,
– relationships among retrieved documents, and
– relationships between retrieved documents and
metadata.
Reduce Working Memory Load
Don’t make users remember – they have
enough to do already.
Information retrieval interfaces might:
– Maintain a history of searches/interactions
– Provide browsable information (collection list,
index terms, thesaurus, …)
– Make suggestions based on
• user history,
• knowledge of task,
• knowledge of collection and retrieved documents.
Alternative Interfaces for Novice
and Expert Users
The first time user, the casual user, and
the regular user need different support.
Inverse relationship between ease-of-use
and user’s control (e.g. specification of
details of ranking approach)
Scaffolding used to support users moving
between interfaces (the interfaces do
not need to be independent)
Role of Visualization
Humans are highly attuned to images and
visual information.
Data (scientific) visualization tends to use
physical intuitions of users.
Information visualization of abstract concepts
(e.g. document space) is more complex.
Information Visualization
Techniques
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Icons and color highlighting
Brushing and linking
Panning and zooming
Focus-plus-context
Magic lenses
Animation (trees and hierarchies)
Evaluating Interactive Systems
Empirical data involving human users is time
consuming to gather and difficult to draw
universal conclusions from.
Evaluation metrics for user interfaces
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Time required to learn the system
Time to achieve goals on benchmark tasks
Error rates
Retention of the use of the interface over time
User satisfaction
Models of Interaction
Information need
Query
Traditional Model:
Send to System
Reformulate
Receive Results
Evaluate Results
What is wrong?
No?
Done?
Yes
Stop
Traditional Model of Interaction
This model assumes that
– the user´s information need is static and
– the information seeking process is one of
successively refining a query the
– ends when until the query retrieves all and
only those documents relevant to the
original information need.
Traditional Model of Interaction
In reality:
– Users learn during search process.
– Scanning/reading is interlaced with search.
– Users browse/examine collection
overviews.
– User navigation makes near misses
valuable.
More Realistic Model
Berry-Picking Model
– Users’ information needs change as they
read/learn.
– As a result their queries change.
– User needs are not satisfied by a single final set of
documents
– They are satisfied by selections of information
found during the process.
The goal is not to generate a query that returns
the right information, but for the user to see
the right information.
Interfaces Support this Process
Given the berry-picking model, the interface
should:
– allow users to reassess their goals and adjust their
search strategy accordingly.
– support search strategies by making it easy to
follow trails with unanticipated results.
– support methods for monitoring the status of the
current strategy in relation to the user’s current
task and high-level goals.
– Some techniques: scanning, querying, navigating,
browsing...
Non-Search Parts of Process
Information seeking is only one part of users’ full
information work process.
Users also read, annotate, and analyze documents.
One study found 80% of work to be:
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Finding trends,
Making comparisons,
Aggregating information,
Identifying a critical subset,
Assessing, and
Interpreting.
Interfaces for More than Search
It is convenient to divide the access
process into two main components:
– search/retrieval
– analysis/synthesis
Interfaces should allow tight integration of
these two activities.
Early IR Interface Studies
Modern systems versus old systems.
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Full text versus bibliographic citations.
Statistical rankings versus Boolean systems.
End users versus professional intermediaries.
Online collections versus separated collections.
Graphic displays versus text displays.
Despite these differences, some general
information seeking strategies have been
identified that seem to transfer across systems.
Some old problems were resolved but new
problems were introduced.