CP684

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CP684

• Human Factors in Information Systems

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From an IT point of view...

• These slides are to be used in conjunction with
  material presented by Drs Aidman and McLachlan
  and the theory contained in your textbook
• Where possible, examples of good/bad design will
  be shown

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Human Factors

• Human Computer Interaction
• Ergonomics
• Human Engineering
• designing for human use
• in the past the user and user behaviour came
  second to machine and machine behaviour

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User-centred approach to design

• Few programs exhibit good interface design.
• It is important that the basic rules for all good
  interfaces are understood
• control should remain with the user
• User input requires almost instantaneous response
  
• Half of the design process is analysis and
  creation the other half is seeking feedback and
  applying its lessons

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What is an Interface?

• Contrary to popular believe it is NOT the
  computer program itself!
• It is the interaction between the program the
  user
• early days - text-based interfaces
• these days - Graphical User Interfaces

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GUIs

• Sometimes referred to as WIMP (windows, icons.
  Mouse, pointer)
• Creation of the illusion of a virtual world
  containing objects to manipulate
• extensive use of metaphors

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Metaphors

• try to represent something new in terms of
  something more familiar, or easier to understand.
  
• Windows Desktop
• Quickens chequebook
• useful in learning an application
• Use of metaphors can become frustrating when
  inappropriately applied.
• Example

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• To eject a diskette on an Apple system one needs
  to drag the diskette icon onto the equivalent of
  the Windows Recycle bin Trash can
• Trash can/Recycle bin is normally used to DELETE
  files
• The user is confused because of the ambiguity of
  the metaphor used.

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• research seems to indicate that GUIs have the
  following advantages over Text (Command Driven
  like DOS) interfaces
• user completes tasks faster
• user has lower level of frustration
• Perceived lower fatigue
• better able to self-teach - reduced training
  costs
• better able to learn more capabilities of
  applications

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Proven GUI design principles

• Understand People
• Design for Clarity
• Design for Consistency
• Provide Visual Feedback
• Provide Audible Feedback
• Keep Text Clear
• Provide Traceable Paths
• Provide Keyboard Support

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...

• Ultimately the success of a GUI design depends on
  how the user will enjoy working with it on a
  day-to-day basis
• Lets look at some of the principles how they
  were applied (or not) in the current GUI
  environment of Windows

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Understand People

• People learn more easily by recognition than by
  recall.
• Always attempt to provide a list of data values
  to select from rather than have the users key in
  values from memory.
• The average word recall is about 2,000 to 3,000
  words
• Word recognition is more than 50,000 words.
• But dont overdo - see next example

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• Word 6.0 (and other versions) know exactly what
  files they are dealing with.
• However, a filetype other than .doc produces the
  dialog box on the right
• Most users would not know nor would they care!

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Design for Clarity

• the amount of light that passes through the eye
  of a sixty year-old is only one-third of that
  passing through the eye of a twenty year-old.
• Quicktimes control window may cause problems
• this toolbar allows for 4 different types of
  Send - but what is what?

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Design for Consistency

• Microsoft Office 2000 completely ignores this
  design principle
• Result is confusion for long-term users of Office
  suite programs

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example

• Where to now?

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Another example

• What does Cut from the Edit menu normally do?
• The selected text or object is removed
• In Excel this is what happens
• a moving border is drawn around the selection
  and nothing happens!
• Confusion reigns as all other programs would have
  removed the selection

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Provide Visual Feedback

• Confirmation dialogs that make sense but NOT
• OR this one!

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But definitely...

• MRU - most recently used files
• tooltips
• On startup
• And options, options, options...

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Provide Audible Feedback

• Keep sound limited to short crisp noises
• rude noises are funny - once - after that they
  become boring
• Dont play Beethovens 9th when all people want
  to do is exit the program!

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Keep Text Clear
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Vision impairment

• Sans-serif typefaces are effective.
• Condensed typefaces are not as effective.

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avoid

• On the left - normal vision
• On the right - the vision-impaired view of same

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!
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Provide Traceable Paths

• It is impossible to work out what drive these
  files and folders reside on!

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WWW - GUI in disguise

• Using the information on the previous slides,
  surf the Internet
• observe the principles mentioned at work
• more importantly, identify those that have not
  been adhered to
• observation of existing design can teach you a lot

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HCI changes...

• First there were switches
• then paper tape
• then punch cards
• followed by dumb terminals
• intelligent terminals
• Point-and-Click
• direct manipulation
• what next?!