TYPING PERFORMANCE OF BLIND USERS HUGO NICOLAU KYLE MONTAGUE TIAGO GUERREIRO ANDRÉ RODRIGUES VICKI L. HANSON
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
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