typing performance of blind users: an analysis of touch behaviors, learning, and in-situ usage
TRANSCRIPT
TYPING PERFORMANCE OF
BLIND USERS HUGO NICOLAU
KYLE MONTAGUETIAGO GUERREIRO
ANDRÉ RODRIGUESVICKI L. HANSON
accessibility :: explore by touch
“Messages. Double-tap to open”
text-entry :: explore by touch
previous :: alternative techniques
Bonner et al., 2010
Azenkot et al., 2012
Oliveira et al., 2011
Southern et al., 2012
Yfantidis et al., 2006
Guerreiro et al., 2015
problem:: lack of understanding
Words per Minute
Error Rate
problem:: how to improve?
?
??
?
contribution :: new knowledge
contribution :: how? why?1 2 3 4 5 6 7 8
1.6 4.0Wor
ds p
er M
inut
e
contribution :: longitudinal study
8
weeks
participants:: novice
5users
apparatus :: S3 mini
procedure :: weekly assessment
week week week week week week week week
20-minute typing tasks
apparatus :: in-situ usage
TinyBlackBoxSupporting Mobile In-The-Wild Studies
results
words per minutehow?
performance :: words per minute
1 2 3 4 5 6 7 81
2
3
4
5
P2P4P1P3P5
Wor
ds p
er M
inut
e
performance :: words per minute
1 2 3 4 5 6 7 81
2
3
4
5
P2P4P1P3P5
Wor
ds p
er M
inut
e
performance :: words per minute
1 2 3 4 5 6 7 81
2
3
4
5
P2P4P1P3P5
Wor
ds p
er M
inut
e
performance :: words per minute
1 2 3 4 5 6 7 81
2
3
4
5
P2P4P1P3P5
Wor
ds p
er M
inut
e
words per minutewhy?
wpm :: land-on accuracy
27% (SD=12)
48% (SD=15)
week 1 week 8
wpm :: movement efficiency
P1 Week 1 P1 Week 8
wpm :: less re-entries
1 2 3 4 5 6 7 8
6.60.8
week
error rateshow?
performance :: total error rate
1 2 3 4 5 6 7 80%
10%
20%
30%
40%
50%P1P2P3P4P5
performance :: uncorrected error rate
1 2 3 4 5 6 7 80%
5%
10%
15%
20%
25%P1P2P3P4P5
performance :: corrected error rate
3 out of 10deleted characters
were correct
performance :: correction time
1 2 3 4 5 6 7 8
32 13Corr
ectio
n Ti
me
(%)
types of errors :: performance
1 2 3 4 5 6 7 80%
5%
10%
15%
20%
25% SubstitutionsOmissionsInsertions
substitutionswhy?
types of errors :: slips
38%
types of errors :: feedback delay
64%
substitutions :: key not visited
36%
major results
summary :: major results
Improve performance at slow rate Due to several factorsSubstitutions are predominantCorrect most errors Corrections are time consuming
summary :: major results
Improve performance at slow rate Due to several factorsSubstitutions are predominantCorrect most errors Corrections are time consuming
summary :: major results
Improve performance at slow rate Due to several factorsSubstitutions are predominantCorrect most errors Corrections are time consuming
summary :: major results
Improve performance at slow rate Due to several factorsSubstitutions are predominantCorrect most errors Corrections are time consuming
summary :: major results
Improve performance at slow rate Due to several factorsSubstitutions are predominantCorrect most errors Corrections are time consuming
implications
correction :: easier and efficient
synchronization :: output and input
“H”“B”
“N”
“M”
touch models :: leverage movement
HUGO NICOLAUhttp://web.ist.utl.pt/hugo.nicolau
TYPING PERFORMANCE OF BLIND USERS
SOS