Case Studies - Measuring the User Experience: Collecting, Analyzing, and Presenting Usability Metrics - page 250

Non-overlay Overlay

250

217 214

200

160

150

132

101

95

100

76

51

50 25

67

46

17

19

5 10

53 41

16

0

1

10

1

20 6

42 32

RS

4

16 7

LS

RT 7 20

18

LT

RS

LS 5

RS

LS

Press more

RS

LS

Less than
four

RS

LS

Spread too
wide

RS

LS

Move left

RS

LS

Move right

Move up

Move down

Figure 10.8 Most common correction errors.

Non-overlay(NFIQ) Overlay(NFIQ) Non-overlay (US-VISIT) Overlay (US-VISIT)

5 100%

90%

87.50%

4 80%

77.50%

78.80%

76.30%

68.40%
66.30%

68.80%
67.50%

70%

3 60%

50%

2 40%

30%

1 20%

10%

0 0%

Thumb Index Middle Ring Little Slap Thumb Index Middle Ring Little Slap

Right Left

Figure 10.9 Fingerprint image quality.

TASK COMPLETION TIME
Task completion time is the total time spent to complete a capture task of four
fingerprint images. As in Table 10.3 , on average, it took participants approxi-
mately 1½ minutes to complete a self-capture task, including four fingerprint
images.