ECOVAL: A Framework for Increasing the Ecological Validity in Usability Testing

46
Suzanne Kieffer ECOVAL: A Framework for Increasing the Ecological Validity in Usability Testing Jean Vanderdonckt Ugo Braga Sangiorgi Université catholique de Louvain Louvain School of Management Louvain-la-Neuve, Belgium

Transcript of ECOVAL: A Framework for Increasing the Ecological Validity in Usability Testing

Suzanne Kieffer

ECOVAL: A Framework for Increasing the Ecological Validity in Usability Testing

Jean VanderdoncktUgo Braga Sangiorgi

Université catholique de Louvain

Louvain School of Management

Louvain-la-Neuve, Belgium

Ecological validity

Experimental design

Natural setting

x x

xxx

xxx

xx

xx

xx

xx

Environment

Tasks

Stimuli

Ecological validity

High

Low

Experimental design

Natural setting

Experimental design

Natural setting

Internal validityWas the study well done?

External validityCan we generalize the findings to particular persons, settings and times?

Ecological validityTo which extent can we generalize the findings?

User interface design

Ecological validity

Overall validity

Conclusionsof usability evaluations

What’s the problem with ecological validity?

No formal definition that enables

To objectively quantify the ecological validity of experimental designs

To capture the critical attributes of the real-world environment

LOGICAL IDITYVALECO ECOVALA framework for increasing the ecological validity in usability testing

Outline

The ECOVAL framework ECOVAL Guidelines GAMBIT

Case study Operability and usefulness of ECOVAL ROI of increased ecological validity Recommendations

The ECOVAL framework

The guidelines

No objects

Mock objects

Real objects

Only verbalized

Mimicked/verbalized

For real

GAMBIT – the supporting tool

Production of prototypes Easy Quick Cost-effective

Real user interface performances Interaction Navigation Responsiveness

GAMBIT – how to

1

Produce screens

GAMBIT – how to

2

Create behaviour

GAMBIT – how to

3

Conduct experiment

GAMBIT – how to

4

Download log file

• Q1: To which extent is ECOVAL applicable for controlling the ecological validity?

• Q2: What are the possible outcomes/benefits of increased ecological validity ?

Case study

Hot-Dip Galvanizing on Continuous Lines

Monitoring report

Task Control Result

Task Control Result

Artefact:paper checklist

Section > Subsection

Function – Name - Date – Shift

Section > Subsection

300 items a day

Monitoring report

Task Control Result

Task Control Result

Artefact:paper checklist

Section > Subsection

Function – Name - Date – Shift

Section > Subsection

Timeline

Task analysis

User profile

Usability goal

setting

Screen design

Usability evaluation

Usability evaluation

Paper versus GAMBIT prototype

Ecological validity

Ratio Paper-to-Gambit for ecological validity of 1:1.17

Balsamiq mockups

Experimentations

Paper GAMBIT

5 key users x 2

10 participants (30’) 18 participants (1 hour)

5 key users x 3+ 3 user representatives

V16 participants

V212 participants

New version of the prototype

Apparatus

Results and discussion

Early detection of usability problems Increased user efficiencies Increased user satisfaction

Cost-benefit analysis

130 hours

18 hours

Cost-benefit analysis (continued)

$74,480

$194,480

Paper GAMBIT

Ecologicalvalidity

1 1.17

Datacollection

Manual & face-to-faceDifficult & tedious Unstructured processObtrusive

Automated & remoteComfortableStructured processUnobtrusive

OutcomesCompliant withthe literature

Early detection of usability problemsIncreased user productivityDecreased late design changesIncreased organizational efficiency

Recommendations

Take away

{ECOVAL, Guidelines, GAMBIT}

Case study Operability Usefulness ROI

Recommendations