CSC 8570 USI

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CSC 8570 -- USI

• Class Meeting 4
• September 13, 2006

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Notations for Actions

• Actions for a keyboard and graphical input device
  (GID) include
• Tap pressing and immediately releasing a key.
  Implemented with a momentary contact
  (spring-loaded) switch.
• Click Position the GID and tap the GID button.
• Double click Position the GID and tap the GID
  button twice quickly, without repositioning.

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Notation for Actions (2)

• Keystroke Level Model
• K , a keystroke. E.g. Kb means tapping lower
  case b
• P, pointing. E.g. positioning the GID
• H, homing. E.g. moving from keyboard to GID or
  GID to keyboard
• M, mental processing
• R, responding

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Notations for Action (3)

• What does the description
• To create a right justified paragraph, use
  Control .
• ask you to do?

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Notations for Action (4)

• More actions
• Press and hold a key
• Release a key
• But on what signal or input?

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Notations and Actions (5)

• Raskin/Beck
• Press and hold bi
• Release bh
• Tap bibh, shortened to bih or just b
• Release on signal bh
• Note that key names are italicized
• Examples
• Create an upper case M ShiftimimhShifth,
  shortened to Shiftimihh

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Notations for Action (6)

• Examples (continued)
• Distinguish between Enter and E n t e r Enter is
  the name of a key and E n t e r is short for
  Eihnihtiheihrih
• bih20 gives a string of bs
• CtrliAltiDelihhh brings up the Task Manager

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Clock Setting

• Set the clock one hour earlier, the common action
  at the end of daylight savings time.
• GOMS model
• Goal stated above
• Operations
• Methods
• Selection Rule

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Bad Interfaces

• Detectable with GOMS model?

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Interfaces and Widgets

• What can a user do? When? Where?
• How effectively?
• Catalog of interface actions
• Catalog of interface widgets

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Modeling Actions

• Task analysis temporal issues
• GOMS analysis method issues
• Keystroke level operator issues

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Task Analysis

• Describes the process the user chooses to reach a
  goal in a specific domain
• Hierarchical description, typically
• Task modeling systems
• GOMS (?)
• ConcurTaskTrees
• UAN (User Action Notation)

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Research Project

• Hypotheses (tonight)
• Independent variables (tonight)
• Dependent variables (tonight)
• Bibliography (next week)
• Background
• Formal setting (lets talk)

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Theory Collection

• Visual processing
• Three-stage visual system
• Preattentive processing theory
• Structured object perception theory (Biederman)
• Scientific color theory (CIE)

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Theory Collection (2)

• Motor Behavior Models
• Hick-Hyman Law choice time
• Keystroke-Level Model error-free task completion
  time
• Three-state model of graphical input (Buxton)
• Fitts Law human movement
• Guiards Model of Bimanual Skill

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Theory Collection (3)

• Task analysis
• Hierarchical model using ConcurTaskTrees

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Research Project (2)

• Experimental design
• Between subjects
• Within subjects
• Sources of bias
• Sources of subjects
• Logic of conclusions

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Research Project (3)

• Institutional Review Board (IRB)
• IRB form
• Informed consent

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Research Project (4)

• Short presentation
• One spokesperson
• Five minutes
• Hypothesis, variables, initial experimental
  design
• PowerPoint or transparencies

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Next Time

• Read Carroll, Chapter 6. Note that this chapter
  describes several spaces.
• Create a concept map that shows the relationships
  between these spaces. Make sure your map is
  labeled with your name so that it can be
  submitted.
• Submit a revised IRB form and bibliography.
• Research project presentation

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Research Team Meetings