1. An ACT-R Modeling
Framework for Interleaving
Templates of Human
Behavior
Michael Matessa
DongNyeok Jeong

2. ACT-R Modeling
• Cognitive architecture
• Performance modeling
• Psychological theory for reuse at
different levels
• Cannot build all multi-tasking work

3. ACT-Stitch
• CPM-GOMS templates and interleaving
theory into ACT-R
• Perceptual-motor interaction
• Empirically validated
• Reusable template

4. Accurate predictions
• lower-level cognitive
• perceptual
• motor resource use

5. Template (adapted from Gray
and Boehm-Davis, 200)
Moving the cursor the a target and clicking the mouse

6. Macro-Compilation
• ACT-Stitch uses a process of macro-
compilation
• translate CPM-GOMS templates
• Cognitive operator
• ACT-R perceptual-motor commands
• CPM-GOMS perceptual-motor operators

7. ACT-Stitch Details
• Two templates implemented
• Slow-Move-Click
• uncertainty about where the target
appears in each trial
• Fast-Move-Click
• selection of a target at a known
location

8. ACT-Stitch Details (cont.)
• Modeler creates two lists
• Target objects
• Task sequence
• Information viewing
• PERT chart

9. • Production creation
• CPM-GOMS templates : predictions of
cognitive, perceptual, and motor behavior
• 30ms(perception time) + Fitts’ Law +
50ms(finish time)
• Motor Actions + Correct Productions +
Incorrect Productions
= ACT-Stitch productions

10. ACT-Stitch productions
3 Examples pseudo-code
Fast-Move-Click template
ATM task(CPM-GOMS)

11. PERT Chart

12. Discussion
• ACT-Stitch framework
• useful modeling the cognitive, perceptual,
and motor processes involved in HCI
task.
• Simple description of an environment
& task sequence
• Macro-compilation to translate task-level
description of behavior => SIMPLE
• Viewing resource use of the model with
PERT chart tools