HCI Research Project

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HCI Research Project
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Research Paradigms

• Theoretical (in the style of mathematics)
• Mathematical deduction
• Simulation
• Analysis of algorithms
• The researcher
• Checks many examples
• Conjectures a result in the form of a theorem
• Constructs the proof of the theorem from known
  results

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Research Paradigms (2)

• Experimental (in the style of psychology)
• Hypotheses checked with controlled
  experimentation
• The researcher
• Poses hypotheses
• Extensive background reading
• Appropriate theoretical model
• Conducts controlled experiments
• Performs statistical analysis of data
• Draws conclusions

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Sample Research Questions

• Why dont typical users invoke advanced search
  strategies?
• What is the preferred method of making a choice
  from a lengthy list? Note behavior of scroll
  bar, key index
• What is the best semantics for the Tab key
  operating on a Web form?
• What is the best shopping cart checkout design?

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Sample Research Questions (2)

• What features should pie menus have in a
  gesture-based interface?
• How should information scent be shown on search
  reports?
• What intelligent agents are most helpful in a
  tiny interface?
• What ZUI widgets are most helpful for information
  retrieval?

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Questions to Hypotheses

• Key is measurability
• Identify
• Independent variable(s) those things the
  researcher can control
• Dependent variables those things the researcher
  can measure
• Aside What is measurable?

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Measuring Things

• Objectively
• Time to do, to correct, to learn
• Counts tasks performed, errors made
• Distance, or other geometrical attributes
• Text density, complexity, reading level
• Images size, color
• Subjectively
• Preference
• Rating scale

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Good Experimental Design

• Limit number of independent variables
• Limit number of values for each independent
  variable
• Make dependent variables easy to measure
• Develop good working definitions
• Control for external bias
• Guard against learning and practice

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Good Experimental Design (2)

• Base hypotheses on theoretical model
• Phrase hypotheses in measurable terms
• Choose subjects representative of larger group

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Example 1

• From Goren-Bar, What Do Users Prefer
• Hypothesis 1 . users in general will find the
  user-oriented search method as more suitable for
  searching the web, compared to search methods
  that do not consider the user perspective.

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Example 1 (continued)

• Hypothesis 2 Novice and knowledgeable users
  will not have the same response to both search
  approaches.

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Example 2

• From St. Amant, Navigation and Intelligent
  Assistance
• Assume that the precision and recall of an
  intelligent assistant can be controlled.
• Hypothesis 1 Is any assistance better than no
  assistance?

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Example 2 (continued)

• Hypothesis 2 Does task performance change with
  the precision of the assistance? (Precision
  proportion of assistance that is relevant)
• Hypothesis 3 Does task performance change with
  the recall of the assistance? (Recall
  proportion of relevant information that is
  provided)

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Example 3

• From Basgodan, Touch in Shared Virtual
  Environments
• Hypothesis Touch is an essential element in
  performing a task in a shared virtual environment.

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Human Subjects

• Informed consent
• Minimized risks
• Institutional Review Board (IRB)
• Expedited review
• Application form

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Organization

• Teams of two or three
• Membership approved by instructor
• Members choose leader

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Items to be Submitted

• Initial phase
• Team membership preferences
• Hypotheses, independent and dependent variables
• Bibliography
• IRB approval formincludes experimental design
  and materials
• Oral presentation of project

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Items to be Submitted (2)

• Investigative phase
• Progress reports as required
• Final phase
• Draft of Introduction, Background and Theoretical
  Foundation
• Draft of Results, Analysis, Conclusion
• Final report oral and written
• Poster abstract and design

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Research Ideas
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Turning Issues into Research

• Need earlier prompts with some car navigation
  systems
• Help systems need to be helpful
• Should order of input matter?
• Should the system respond after it receives input
  from the user?
• Speech recognition systems are poor, not very
  accurate

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Issues into Research (2)

• Time delays in responding to input are annoying,
  may have high error cost.
• Controls should match mental models
• Systems should display current data and use a
  continuous update strategy
• Error messages should make sense to the user.

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Research Questions

• What is the task analysis of purchasing an
  airplane ticket? How well is it supported by an
  airline website as displayed on a smart phone?
• How should a PDA support a shopping list?
• How can an email interface support task
  management?

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Questions (2)

• How do people manage their digital photographs?
• What is the best interface for a GPS-based
  navigation system?
• What are the features of a good proximity-aware
  recommender system?

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Questions (3)

• What design features promote the success of
  reprogrammable keys? Or of soft keyboards?
• How fast should automatic scrolling of
  information on limited size screens proceed?

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Sources for More Ideas

• CHI Conference Proceedings
• ACM Transactions on HCI
• Course web site