Experiment

1
A Comparison of Map vs. Text Directions for a
Handheld Device in a Campus Setting A Pilot Study
Liz Atwater Department of Psychology George Mason University Jason Burke Institute for Systems Research University of Maryland Andrea Kirk Department of Computer Science University of Maryland
December 2001
2
Map vs. Text Directions

• Which one is more effective?
• Less time, less errors
• Does route complexity have an effect?
• Use by pedestrians instead of drivers
• Lack of landmarks
• No street names, etc.

3
Rover

• Context-aware, location-aware
• Location awareness via GPS, RF, IR, etc.
• Provides information depending on
• User profile
• Device profile
• Location
• Context
• Useful in many domains
• Tourism
• Commerce

4
Background Research

• Williams studies (1999) pilots finding nearest
  airport using maps or text
• Maps are faster and more accurate
• ERF tasks had better results with track-up
• WRF tasks had better results with north-up
• Aretz,1991 ERF vs. WRF
• Ego-centered frame ? track-up
• World-centered frame ? north-up
• Butz, 2001 landmarks at key decision points

5
Experiment Hypotheses

• Hypotheses
• Null There is no statistical difference between
  completion time, consultation time and number of
  errors between text and map directions,
  regardless of route complexity.
• H1 Users will complete the tasks faster using
  map directions.
• H2Users will make fewer errors using map
  directions.
• H3 Users will need less consultation time using
  text directions.
• H4 Completion time will rise with increasing
  route complexity.

6
Experiment Variables

• IVs Treatments
• Direction type map vs. text
• Route complexity low, medium, high
• Low 3 decision points, 893 ft
• Medium 5 decision points, 897 ft
• High 7 decision points, 883 ft
• DVs
• Completion time
• Consulting time
• Errors

7
Experiment Materials

• Subjects
• 7 male, 5 female
• Undergrad grad UMCP students
• Other materials
• Pre post-task questionnaires
• VZ-2

8
Experiment Tasks

• Navigate 3 routes using directions
• Within-subjects for routes
• Between-subjects for direction type
• 2 stopwatches
• Route permutations

123 132
213 231
312 321
9
Screen Shots
Text Implementation
Map Implementation
10
Results Completion Time

• Main effect for route significant
• Main effect for direction ns
• Interaction effect ns

11
Results Consultation Time

• Main effect for route significant
• Main effect for direction ns
• Interaction effect ns

12
Results Errors

• Main effect for route significant
• Main effect for direction ns
• Interaction effect ns

13
Observations

• Learning seemed to have a significant effect on
  the results
• Most errors occurred at non-dead ends
• People are different
• Huge variance in user performance in both map and
  text implementations
• Difficulty judging distances in text version
• Rotate map for track-up bearings
• Looking ahead caused problems

14
Conclusions

• Need many more subjects
• Text directions are difficult to describe in
  college campus environment
• Feedback from real context-aware equipment
  could improve performance
• Track-up display for map could decrease
  orientation time
• Hybrid to accommodate variations in user
  cognitive strengths