A Comparison of Map vs. Text Directions for a Handheld

Device in a Campus Setting: A Pilot Study

Liz AtwaterDepartment of Psychology

George Mason University

Jason BurkeInstitute for Systems

Research

University of Maryland

Andrea KirkDepartment of Computer

Science

University of Maryland

December 2001

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.

Map vs. Text Directions

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

Rover

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

Background Research

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.

– H2:Users 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.

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

Experiment – Variables

Subjects– 7 male, 5 female– Undergrad & grad UMCP students

Other materials– Pre & post-task questionnaires– VZ-2

Experiment – Materials

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

123 132

213 231

312 321

Experiment – Tasks

Screen Shots

Text Implementation Map Implementation

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

Completion Time

0

50

100

150

200

250

300

350

400

High Medium Low

Route complexity

Tim

e (

s)

Map

Text

Results – Completion Time

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

Device Consulting Time

-20

0

20

40

60

80

100

120

High Medium Low

Route Complexity

Tim

e (

s)

Map

Text

Results – Consultation Time

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

Number of Errors

-0.5

0

0.5

1

1.5

2

2.5

3

3.5

High Medium Low

Route Complexity

Nu

mb

er

of

err

ors

Map

Text

Results – Errors

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

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