erfaringer med remote usability testing?
Post on 02-Jan-2016
40 Views
Preview:
DESCRIPTION
TRANSCRIPT
Erfaringer med Remote Usability Testing?
Jan Stage
Professor, PhD
Forskningsleder i Informationssystemer (IS)/Human-Computer Interaction (HCI)
Aalborg Universitet, Institut for Datalogi, HCI-Lab
jans@cs.aau.dk
Institut for Datalogi 2
• Undersøgelse 1
• Undersøgelse 2
Oversigt
Institut for Datalogi 3
• Undersøgelse 1: synkron eller asynkron
• Metode
• Resultater
• Konklusion
• Undersøgelse 2
Oversigt
Institut for Datalogi
Empirical Study 1
Four methods: LAB – RS – AE – AU
Test subjects: 6 in each condition (18 users and 6 with usability expertise), all students at Aalborg University
System: Email client (Mozilla Thunderbird 1.5)
9 defined tasks (typical email functions)
Setting, procedure and data collection in accordance with method
Data analysis: 24 outputs were analysed by three persons in random and different order
Generated their individual lists of usability problems with their own categorizations (also for the AE and AU conditions)
These were merged into an overall problem list through negotiation
4
Institut for Datalogi 5
Results: Task CompletionNo significant difference in task
completion
Significant difference in task completion time
The users in the two asynchronous conditions spent considerably more time
We do not know the reason
Institut for Datalogi 6
Results: Usability Problems Identified
A total of 46 usability problems
No significant difference between LAB and RS
AE/AU identified significantly fewer problems, also critical problems
No significant difference between AE and AU in terms of problems identified
Institut for Datalogi 7
Conclusion
RS is the most widely described and used remote method. The performance is virtually equivalent to LAB (or slightly better)
AE and AU perform surprisingly well
Experts do not perform significantly better than users
Video analysis (LAB and RS) required considerably more evaluator effort than the user-based reporting (AU and AE)
Users can actually contribute to usability evaluation – not with the same quality, but reasonably well, and there are plenty of them
Institut for Datalogi 8
• Undersøgelse 1
• Undersøgelse 2: hvilken asynkron metode
• Metode
• Resultater
• Konklusion
Oversigt
Institut for Datalogi 9
Empirical Study 2
Purpose: examine and compare remote asynchronous methods
Focus on usability problems identified
Comparable with the previous study
Selection of asynchronous methods based on literature survey
Institut for Datalogi 10
The 3 Remote Asynchronous Methods
User-reported critical incident (UCI)• Well-defined method (Castillo et al. CHI 1998)
Forum-based online reporting and discussion (Forum)• Assumption: through collaboration participants may give input which
increases data quality and richness (Thompson, 1999)• A source for collecting qualitative data in a study of auto logging (Millen,
1999): the participants turned out to report detailed usability feedback
Diary-based longitudinal user reporting (Diary)• Used on a longitudinal basis for participants in a study of auto logging to
provide qualitative information (Steves et al. CSCW 2001)• First day: same tasks as the other conditions (first part of diary delivered)• Four more days: new tasks (same type) sent daily (complete diary delivered)
Conventional user-based laboratory test (Lab)• Included as benchmark
Institut for Datalogi 11
Participants:• 40 test subjects, 10 for each condition• Students, age 20 to 30• Distributed evenly: gender and tech/non-tech education
Setting:• LAB: in our usability lab• Remote asynchronous: in the participants’ homes
Participants in the remote asynchronous conditions received the software and installed it on their computer
Training material for the remote asynchronous conditions• Identification and categorisation of usability problems• A minimalist approach that was strictly remote and
asynchronous (via email)
Empirical Study (1)
Institut for Datalogi 12
Tasks:• Nine fixed tasks• The same across the four conditions to ensure that all
participants used the same parts of the system• Typical email tasks (same as previous study)
Data collection in accordance with the method• LAB: video recordings• UCI: web-based system for generating problem descriptions
while solving tasks• Forum: after solving tasks, one week for posting and discussing
problems• Diary: a diary with no imposed structure; first part after the first
day
Empirical Study (2)
Institut for Datalogi 13
All data collected before the data analysis started
3 evaluators did the whole data analysis
The 40 data sets were analysed by the 3 evaluators• In random order: by a draw• In different order between them
The user input from the three remote conditions was transformed into usability problem descriptions
Each evaluator generated his/her own individual lists of usability problems with their own severity ratings• A problem list for each condition• A complete problem list (joined)
These were merged into an overall problem list through negotiation
Data Analysis
Institut for Datalogi 14
Results: Task Completion Time
Considerable variation in task completion times
Participants in the remote conditions worked in their home at a time they selected
For each task there was a hint that allowed them to check if they had solved the task correctly
As we have no data on the task solving process in the remote conditions, we cannot explain this variation
Institut for Datalogi 15
LAB: significantly better than the 3 remote conditions
UCI-Forum: no significant difference
UCI-Diary: significant overall: Diary – also significant on cosmetic
Forum-Diary: significant overall: Diary – not significant on any level
Results: Usability Problems IdentifiedLab
N=10UCI
N=10ForumN=10
DiaryN=10
Task completion time in minutes: Average (SD)
24.24 (6.3)34.45
(14.33)15.45 (5.83)
Tasks 1-9: 32.57
(28.34)
Usability problems: # % # % # % # %
Critical (21) 20 95 10 48 9 43 11 52
Serious (17) 14 82 2 12 1 6 6 35
Cosmetic (24) 12 50 1 4 5 21 12 50
Total (62) 46 74 13 21 15 24 29 47
Institut for Datalogi 16
Results: Evaluator Effort
The sum for all evaluators involved in each activity
Time for finding test subjects is not included (8h, common for all)
Task specifications from an earlier study. Preparation in the remote conditions: work out written instructions
Considerable differences between the remote conditions for analysis and merging of problem lists
Lab (46)
UCI (13)
Forum (15)
Diary (29)
Preparation 6:00 2:40 2:40 2:40
Conducting test 10:00 1:00 1:00 1:30
Analysis 33:18 2:52 3:56 9:38
Merging problem lists 11:45 1:41 1:42 4:58
Total time spent 61:03 8:13 9:18 18:46
Avg. time per problem
1:20 0:38 0:37 0:39
Institut for Datalogi 17
Conclusion
The three remote methods performed significantly below the classical lab test in terms of the number of usability problems identified
The Diary was the best remote method – it identified half of the problems found in the Lab condition
UCI and Forum performed similarly for critical problems but worse for serious problems
UCI and Forum took 13% of the lab test. Diary took 30%
The productivity of the remote methods was considerably higher
Institut for Datalogi 18
Institut for Datalogi
Interaktionsdesign og usability-evaluering
Master i IT
Videreuddannelse under IT-Vest
Fagpakke i Interaktionsdesign og usability-evaluering starter 1/2-12
Optager bachelorer, men også indgang for datamatikere
Information: http://www.master-it-vest.dk/
19
top related