Task Analysis

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Task Analysis

• Organizing and understanding activities

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Agenda

• Questions
• Read MacKenzie paper
• Task analysis
• history techniques
• Hierarchical TA
• Knowledge-Based TA
• Entity-Relationship TA

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Recap

• Fight your assumptions
• Observation / Interview
• watch, ask , interpret, repeat
• Apprentice Model
• Triangulation
• other data experts, documentation

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Other techniques

• Exercises
• Sorting, ordering
• Focus groups
• Reaction to prototypes
• Surveys
• Detailed data, evaluation

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Consent

• Subjects informed agreement
• What will happen?
• What are the benefits / risks?
• Withdrawl at any time is allowed
• Guardian consent
• Education project exempt
• Samples on co-web

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Task analysis

• Process of analyzing and documenting how people
  perform their jobs
• History (see Web)
• turn of the century Taylorism
• Gilbreth
• Miller (1953)

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Overview

• Describing how people do their work
• activities
• artifacts
• relations

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Relationship to Cognitive Models

• TA has higher level of abstraction
• especially compared to KLM
• External/objective viewpoint

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Different techniques

• Decomposition
• Knowledge-based / taxonomic
• Entity-Relationship

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Sources

• Documentation
• Observation/Interviews
• Participative exercises

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Uses

• System analysis / Requirements
• Instructional manuals (users guide)
• Menu design

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Task decomposition

• HTA
• Breakdown plan

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Using HTA for analysis

• Properties of the decomposition
• imbalanced
• complicated plans

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Knowledge-based

• TAKD
• taxonomic (unique categorizations of items and
  actions)
• good for menu design understanding problem
  language

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Entity-Relationship

• Similar to OO design
• Identify object-action relations

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Task analysis in project

• Must perform one formal TA
• How to choose?

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Upcoming

• Wednesday (9/12) Motor behavior, Predictive
  models
• Friday (9/14) Videos
• Monday (9/17) Cognitive Models
• Wednesday (9/19) GOMS, User Models
• Friday (9/21) Project Part 1 Due