B Identification Flats (“ThreeInch” Data)

B.1 Bootstrap Confidence for Segmentation Statistics

This section shows the same detailed results of segmentation of ThreeInch data from Section 3.3, but with an added bootstrap confidence interval. For each observation, a bootstrap routine with 1 000 replicates was run, and a 95 % confidence interval extracted. The lower and upper confidence from that confidence interval are printed in each column within square brackets.

In Table B.1, results are shown of how successful DecaturImp+0004 segmented fingers for each subject in the test corpus. Table B.2 shows success for specific finger positions over the entire test corpus. Similarly, Table B.3 shows success for segmenting the same finger position from both hands.

The remainder of the tables show success per subject when considering combinations of subsets of the fingers in each slap image. Table B.4 shows success for combinations of all fingers, Table B.6 for the all except the little finger, and Table B.5 for just the index and middle fingers.

Table B.1: For each subject, the percentage that at least Number of Fingers fingers were correctly segmented, regardless of hand, for a maximum of eight correctly-segmented fingers. In Standard Scoring, scoring rules are followed exactly. In Ignoring Bottom Y, the bottom left and bottom right Y coordinates are ignored. Ignoring Bottom X and Y only checks the locations of the top left and top right coordinates. Values in square brackets represent a 95 % confidence interval after bootstrapping with 1 000 replicates.
Number of Fingers Standard Scoring Ignoring Bottom Y Ignoring Bottom X and Y
1 99.6 [99.5, 99.7] 99.7 [99.6, 99.7] 99.7 [99.6, 99.7]
2 98.7 [98.5, 98.8] 99.0 [98.9, 99.1] 99.0 [98.9, 99.1]
3 97.4 [97.3, 97.6] 98.4 [98.2, 98.6] 98.4 [98.3, 98.6]
4 95.8 [95.5, 96.0] 98.0 [97.8, 98.2] 98.1 [97.9, 98.3]
5 92.3 [92.0, 92.6] 95.9 [95.6, 96.1] 95.9 [95.6, 96.1]
6 88.4 [88.0, 88.8] 95.8 [95.6, 96.1] 95.8 [95.6, 96.1]
7 82.0 [81.6, 82.5] 95.6 [95.4, 95.9] 95.7 [95.4, 95.9]
8 72.5 [71.9, 73.0] 94.8 [94.6, 95.1] 95.0 [94.8, 95.3]
9 56.8 [56.2, 57.4] 89.1 [88.7, 89.5] 90.0 [89.6, 90.3]
10 32.7 [32.0, 33.2] 65.9 [65.2, 66.4] 68.0 [67.5, 68.6]
Table B.2: For all subjects, Percentage that a particular friction ridge generalized position was correctly segmented. In Ignoring Bottom Y, the bottom left and bottom right Y coordinates are ignored. Ignoring Bottom X and Y only checks the locations of the top left and top right coordinates. Values in square brackets represent a 95 % confidence interval after bootstrapping with 1 000 replicates.
Finger Standard Scoring Ignoring Bottom Y Ignoring Bottom X and Y
Right
Thumb 79.7 [79.2, 80.2] 85.7 [85.3, 86.2] 86.6 [86.2, 87.1]
Index 93.6 [93.3, 93.9] 99.2 [99.0, 99.3] 99.3 [99.2, 99.4]
Middle 78.8 [78.3, 79.3] 99.2 [99.1, 99.3] 99.4 [99.3, 99.5]
Ring 79.6 [79.1, 80.1] 98.1 [98.0, 98.3] 98.3 [98.2, 98.5]
Little 92.2 [91.8, 92.5] 97.1 [96.9, 97.3] 97.4 [97.2, 97.6]
Left
Thumb 76.9 [76.4, 77.4] 84.2 [83.8, 84.7] 85.1 [84.7, 85.6]
Index 91.3 [91.0, 91.7] 98.0 [97.9, 98.2] 98.2 [98.0, 98.3]
Middle 75.3 [74.8, 75.9] 99.1 [99.0, 99.2] 99.3 [99.2, 99.4]
Ring 79.0 [78.5, 79.5] 99.0 [98.9, 99.1] 99.2 [99.1, 99.3]
Little 91.4 [91.1, 91.7] 98.3 [98.1, 98.5] 98.6 [98.5, 98.8]
Table B.3: Percentage that a particular type of fingerprint was correctly segmented on Either or Both hands. In Ignoring Bottom Y, the bottom left and bottom right Y coordinates are ignored. Ignoring Bottom X and Y only checks the locations of the top left and top right coordinates. Values in square brackets represent a 95 % confidence interval after bootstrapping with 1 000 replicates.
Fingers Standard Scoring Ignoring Bottom Y Ignoring Bottom X and Y
Thumb
Either 91.6 [91.3, 91.9] 95.9 [95.6, 96.1] 96.2 [96.0, 96.5]
Both 65.0 [64.4, 65.6] 74.1 [73.6, 74.7] 75.6 [75.0, 76.1]
Index
Either 97.6 [97.5, 97.8] 99.8 [99.7, 99.8] 99.8 [99.7, 99.8]
Both 85.0 [84.5, 85.4] 94.8 [94.5, 95.0] 95.0 [94.7, 95.3]
Middle
Either 87.6 [87.1, 88.0] 99.7 [99.7, 99.8] 99.8 [99.7, 99.9]
Both 64.8 [64.2, 65.4] 95.9 [95.6, 96.1] 96.3 [96.0, 96.5]
Ring
Either 89.6 [89.2, 89.9] 99.7 [99.7, 99.8] 99.8 [99.7, 99.8]
Both 67.1 [66.5, 67.6] 94.7 [94.4, 95.0] 95.1 [94.8, 95.4]
Little
Either 97.5 [97.3, 97.7] 99.5 [99.4, 99.6] 99.5 [99.5, 99.6]
Both 83.7 [83.3, 84.2] 93.3 [93.0, 93.6] 93.9 [93.6, 94.2]
Table B.4: Percentage of segmentation success by hand for combinations of all ten fingers of a ThreeInch slap. In Ignoring Bottom Y, the bottom left and bottom right Y coordinates are ignored. Ignoring Bottom X and Y only checks the locations of the top left and top right coordinates. Values in square brackets represent a 95 % confidence interval after bootstrapping with 1 000 replicates.
Fingers Standard Scoring Ignoring Bottom Y Ignoring Bottom X and Y
Right
Any 99.1 [99.0, 99.1] 99.3 [99.3, 99.4] 99.3 [99.3, 99.4]
At Least Two 96.8 [96.4, 96.7] 98.5 [98.3, 98.6] 98.5 [98.3, 98.6]
At Least Three 91.5 [90.2, 90.7] 98.2 [98.1, 98.4] 98.3 [98.2, 98.4]
At Least Four 78.5 [76.6, 77.3] 96.7 [96.6, 96.9] 97.0 [96.9, 97.2]
All Five 50.2 [47.8, 48.8] 77.9 [77.2, 77.9] 79.4 [78.6, 79.3]
Left
Any 99.0 [99.0, 99.1] 99.4 [99.3, 99.4] 99.4 [99.3, 99.4]
At Least Two 96.2 [96.4, 96.7] 98.4 [98.3, 98.6] 98.4 [98.3, 98.6]
At Least Three 89.4 [90.2, 90.7] 98.2 [98.1, 98.4] 98.3 [98.2, 98.4]
At Least Four 75.4 [76.6, 77.3] 96.8 [96.6, 96.9] 97.1 [96.9, 97.2]
All Five 46.3 [47.8, 48.8] 77.1 [77.2, 77.9] 78.5 [78.6, 79.3]
Table B.5: Percentage of segmentation success by hand when only considering combinations of index and middle fingers. In Ignoring Bottom Y, the bottom left and bottom right Y coordinates are ignored. Ignoring Bottom X and Y only checks the locations of the top left and top right coordinates. Values in square brackets represent a 95 % confidence interval after bootstrapping with 1 000 replicates.
Fingers Standard Scoring Ignoring Bottom Y Ignoring Bottom X and Y
Right
Either Index or Middle 96.4 [95.4, 95.8] 99.9 [99.8, 99.9] 99.9 [99.8, 99.9]
Both Index and Middle 76.0 [73.5, 74.3] 98.5 [97.8, 98.0] 98.8 [98.1, 98.4]
Left
Either Index or Middle 94.8 [95.4, 95.8] 99.8 [99.8, 99.9] 99.8 [99.8, 99.9]
Both Index and Middle 71.8 [73.5, 74.3] 97.3 [97.8, 98.0] 97.6 [98.1, 98.4]
Table B.6: Percentage of segmentation success by hand when only considering combinations of index, middle, and ring fingers. In Ignoring Bottom Y, the bottom left and bottom right Y coordinates are ignored. Ignoring Bottom X and Y only checks the locations of the top left and top right coordinates. Values in square brackets represent a 95 % confidence interval after bootstrapping with 1 000 replicates.
Fingers Standard Scoring Ignoring Bottom Y Ignoring Bottom X and Y
Right
Any 97.7 [97.0, 97.3] 99.9 [99.9, 99.9] 99.9 [99.9, 99.9]
At Least Two 87.2 [85.8, 86.4] 99.7 [99.6, 99.7] 99.7 [99.6, 99.7]
All Three 67.1 [65.1, 66.0] 96.9 [96.6, 96.9] 97.4 [97.1, 97.4]
Left
Any 96.7 [97.0, 97.3] 99.9 [99.9, 99.9] 99.9 [99.9, 99.9]
At Least Two 85.0 [85.8, 86.4] 99.6 [99.6, 99.7] 99.7 [99.6, 99.7]
All Three 63.9 [65.1, 66.0] 96.6 [96.6, 96.9] 97.1 [97.1, 97.4]

B.2 Jaccard Index

Boxplot of Jaccard similarity indices as compared to the traditional success metrics. Outliers have been removed for clarity.

Figure B.1: Boxplot of Jaccard similarity indices as compared to the traditional success metrics. Outliers have been removed for clarity.

Boxplot of Jaccard similarity indices for each friction ridge generalized position. Outliers have been removed for clarity.

Figure B.2: Boxplot of Jaccard similarity indices for each friction ridge generalized position. Outliers have been removed for clarity.

Table B.7: For each subject, the percentage that at least Number of Fingers fingers were segmented with a Jaccard index in the indicated range.
Number of Fingers ≥0.5 ≥0.6 ≥0.7 ≥0.8 ≥0.9 ≥0.95 ≥0.98
1 99.9 99.9 99.9 99.5 92.8 61.4 26.1
2 99.9 99.7 99.4 98.2 83.4 33.3 6.4
3 98.4 98.2 97.6 95.7 71.1 16.0 1.2
4 98.1 97.6 96.3 92.6 57.9 6.7 0.2
5 95.9 95.6 93.5 87.6 44.5 2.6 0.0
6 95.8 95.0 90.8 81.2 31.8 0.8 0.0
7 95.7 94.0 86.3 72.7 20.3 0.2 0
8 95.4 91.5 79.2 61.4 10.8 0.0 0
9 94.3 86.3 68.0 45.7 4.0 0 0
10 89.6 73.6 48.5 25.8 0.9 0 0
Table B.8: For all subjects, percentage that a particular friction ridge generalized position was segmented with a Jaccard index in the indicated range.
Finger 0-0.5 0.5-0.6 0.6-0.7 0.7-0.8 0.8-0.9 0.9-1.0
Right
Thumb 1.3 0.8 5.4 15.4 43.8 33.3
Index 0.5 1.6 3.6 4.6 27.5 62.2
Middle 0.9 4.9 11.6 10.1 22.5 50.0
Ring 0.9 5.1 11.5 11.5 31.8 39.2
Little 1.2 2.6 2.8 10.6 49.5 33.3
Left
Thumb 1.3 1.1 7.7 16.1 39.7 34.1
Index 0.6 2.6 3.8 4.9 35.3 52.8
Middle 1.0 6.1 13.1 10.6 26.4 42.8
Ring 0.9 5.2 11.6 10.6 30.7 41.0
Little 1.6 3.3 3.1 7.9 45.9 38.2
Table B.9: Percentage of segmentation obtaining a Jaccard index in the indicated ranges, by hand, for combinations of all ten fingers of a ThreeInch slap.
Fingers ≥0.5 ≥0.6 ≥0.7 ≥0.8 ≥0.9 ≥0.95 ≥0.98
Right
Any 99.9 99.9 99.7 98.3 82.5 42.8 15.1
At Least Two 98.5 98.3 97.3 93.0 62.5 15.2 2.2
At Least Three 98.4 97.3 93.4 84.1 42.3 3.8 0.2
At Least Four 97.6 93.9 83.7 68.6 21.9 0.5 0.0
All Five 91.7 82.0 62.9 41.9 5.3 0.0 0.0
Left
Any 99.9 99.8 99.6 98.5 81.3 40.0 14.5
At Least Two 98.4 98.1 96.8 93.3 59.4 14.2 1.9
At Least Three 98.2 96.7 91.8 83.1 38.9 4.0 0.2
At Least Four 97.5 92.7 81.3 66.2 20.1 0.7 0.0
All Five 91.1 79.8 59.2 38.7 5.4 0.0 0.0
Table B.10: Percentage of segmentation obtaining a Jaccard index in the indicated ranges, by hand, for combinations of index and middle fingers of a ThreeInch slap.
Fingers ≥0.5 ≥0.6 ≥0.7 ≥0.8 ≥0.9 ≥0.95 ≥0.98
Right
Either Index or Middle 99.8 99.2 96.7 93.1 72.4 34.2 11.3
Both Index and Middle 98.8 92.9 80.2 69.2 39.9 7.4 0.8
Left
Either Index or Middle 99.8 98.6 95.7 92.0 64.4 26.0 9.2
Both Index and Middle 98.5 91.0 77.1 65.3 31.2 4.5 0.6
Table B.11: Percentage of segmentation obtaining a Jaccard index in the indicated ranges, by hand, for combinations of index, middle, and ring fingers of a ThreeInch slap.
Fingers ≥0.5 ≥0.6 ≥0.7 ≥0.8 ≥0.9 ≥0.95 ≥0.98
Right
Any 99.9 99.5 97.9 94.7 75.6 37.6 13.2
At Least Two 99.6 97.1 89.3 80.2 50.6 11.2 1.5
All Three 98.2 89.6 72.3 58.3 25.5 1.8 0.1
Left
Any 99.9 99.2 97.2 94.5 70.6 32.0 11.7
At Least Two 99.6 96.3 87.7 78.7 44.8 9.1 1.2
All Three 97.9 87.9 70.0 55.9 21.2 1.6 0.1