Heuristics

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Heuristics

• Bob Phillips
• February 28, 2000

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Heuristics Defined

• A rule of thumb, a simplification, or an educated
  guess that reduces or limits the search for
  solutions in domains that are difficult and
  poorly understood. Unlike algorithms, heuristics
  do not guarantee optimal, or even feasible
  solutions, and are often used with no theoretical
  guarantee.
• The Free Online Dictionary of Computing

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Usability Heuristics Principles

• Simple and Natural Dialogue
• Speak the Users Language
• Minimize User Memory Load
• Strive for Consistency
• Offer Informative Feedback
• Provide Clearly Marked Exits
• Shortcuts for Frequent Users

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Usability Heuristics Principles

• Good Error Messages / Easy Undo
• Prevent Errors / Simple Recovery
• Help and Documentation
• Heuristic Evaluation
• a.k.a., the Good, the Bad, and the Ugly

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Simple and Natural Dialogue

• Graphic Design and Color
• Less is More

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Good Graphics Designand Color
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Poor Graphics Design 1 Color
Visible to the Elderly? to the Color Blind?
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Poor Graphics Design 2 Color
Visible to the Elderly? to the Color Blind?
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Poor Graphics Design 3 Color
Visible to the Elderly? to the Color Blind?
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Simple Design Less is More
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Simple Design More is Less
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Simple Design More is Less
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Simple DesignPatient-Entered Health Data
Modern left-to-right, single questionblock/page
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Simple DesignPatient-Entered Health Data
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Simple DesignPatient-Entered Health Data
 top-down, single-page
Traditional Interface
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Simple DesignPatient-Entered Health Data
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Speaking the Users Language

• Terminology in user interfaces should be based on
  the users language and not the jargon of health
  care professionals.
• Exception If the interface will be used
  exclusively by health care professionals,
  domain-specific terminology should be utilized.

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Speaking the Users Language
EXAMPLE
NOT otalgia
NOT rhinorrhea
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Minimize User Memory Load

• Whenever users are required to provide input, the
  system should describe the required format and,
  if possible, provide an example of legal and
  sensible input.

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Minimize User Memory Load
EXAMPLE legal and sensible input
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Minimizing Load a Pause
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Interface Consistency
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Interface Consistency
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Poor Feedback IndicatorDifficult to Visualize
Indicator ? ?
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Good Feedback IndicatorEasy to Visualize and
Interpret
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Clearly Marked Exits
Exit ??
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Shortcuts for Frequent Users
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Good Error Message
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Excellent Error Message
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Good Error Message
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Poor Error Message
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Preventing ErrorsMenu Selection
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Online Help and Documentation
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Online Help and Documentation
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Heuristic Evaluation(a.k.a. the Good, the Bad,
and the Ugly)