Why HCI

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Why HCI?
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HCI in Software Development

• Developers Perspective
• Educating Developers
• Educated Developers
• Resources

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Developers Perspective

• The terminal and the end-user, what's the
  difference?

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Educating Developers

• HCI is not part of the traditional(?) education
  program for software developers.
• Typically stop with teaching the programming of
  widgets on the screen.

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Educated Developers

• "Having trained, qualified HI people involved in
  a software effort produces major benefits at a
  most reasonable cost." (Tognazzini)
• Bailey (CHI'93) shows that HCI specialists create
  interfaces that have fewer errors and supported
  faster user execution than interfaces designed by
  programmers.

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Practices

• Early Focus on Users and Tasks
• Empirical Measurement
• Iterative Design

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Evidence (1)

• 447 system planners, designers, and programmers
  were asked to write down the sequence of major
  steps in developing and evaluating a new computer
  system for end users.

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Evidence (2)

• Percent Mentioning Each Principle

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References
Gould, J. D. C. Lewis (1985) Designing for
Usability Key Principles and What Designers
Think. CACM, 28, p. 300-311. Gould, J. D., S. J.
Boies, S. Levy, J. T. Richards, J. Schoonard
(1987) The 1984 Olympic Message System A Test of
Behavioral Prinipcles of System Design. CACM, 30,
p. 758-769.
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Resources

• Myers and Rosson (CHI'92) present data on
  percentage of code that goes into development of
  the interface. The survey incorporated data from
  74 projects ranging from 400 to 5,000,000 lines
  of code over a variety of languages and
  application types.
• average around 48 of the code is interface
• 44.8 of design time
• 50.1 of implementation time
• 37 of maintenance time devoted to UI

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Interface

• A narrow perspective has us thinking of the
  interface as screen design. From a computer
  science perspective, the focus is on interaction
  and specifically on interaction between one or
  more humans and one or more computational
  machines.
• Is there a broader perspective?

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Caveat

• Information Systems change the use context in
  either planned or unplanned ways.

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HCI as a Discipline

• HCI in the large is an interdisciplinary area. It
  is emerging as a specialty concern within several
  disciplines, each with different emphases
• computer science (application design and
  engineering of human interfaces)
• psychology (the application of theories of
  cognitive processes and the empirical analysis of
  user behavior)
• sociology and anthropology (interactions between
  technology, work, and organization
• industrial design (interactive products).

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Content of Human-Computer Interaction

• HCI Perspective