interoperability and the stability score index
DESCRIPTION
The stability score index, conceptualized in 2013, was designed to address the weaknesses of the zoo menagerie and other performance metrics by quantifying the relative stability of a user from on condition to another. In this paper, the measure of interoperability is the stability score from enrolling on one sensor and verifying on multiple sensors. The results showed that like performance, individual performance were not stable across these sensors. When examining stability by sensor family (capacitance, optical and thermal) we find that capacitive as the enrollment sensor were the least stable. Both enrolling and verifying on a thermal sensor, individuals were the most stable of the three family types. With respect to interaction type, enrolling on touch and verifying on swipe was more stable than enrolling on swipe and verifying on swipe, which was an interesting finding. Individuals using the thermal sensor generated the most stable stability scores.TRANSCRIPT
INTEROPERABILITY AND THE
STABILITY SCORE INDEXZach Moore, Stephen Elliott, Kevin O’Connor, Shimon Modi
INTRODUCTION
•Wanted to look at interoperability of fingerprint
images across sensors in the context of
stability
•Quality changes across sensors, but does this
affect stability?
INTRODUCTION
• Shimon, 2008
• Analyzed interoperability of fingerprint sensors
• How this affected system performance
• Minutiae based matching
• O’Connor, 2013
• Looked at the instability of the zoo animals across different force levels
• Created the stability score index (SSI)
RELATED WORK
STABILITY SCORE INDEX
METHODOLOGY
• Cleaned the data
• Only used subjects who had three enrollment captures and three testing captures on all sensors
• Created dataruns
• Ran the data through Megamatcher to get genuine and impostor scores
• Ran the scores through Oxford Wave to get zoo analysis
• Used the zoo analysis to calculate stability scores
METHODOLOGY
•Divided datasets
METHODOLOGY
Sensor Enrollment
Samples
Testing
Samples
Total
Samples
Atmel 483 483 966
Authentec 483 483 966
Crossmatch 483 483 966
Digital Persona 483 483 966
Fujitsu 483 483 966
Futronic 483 483 966
Identix 483 483 966
UPEK S 483 483 966
UPEK T 483 483 966
SAMPLES
• 161 subjects
• 6 captures each
• 3 enrollment
• 3 testing
RESULTS
AVERAGE SSI GROUPING MATRIX
AVERAGE SSI GROUPING MATRIX
SUBJECT 43 STABILITY
SENSOR MATRIX
SENSOR MATRIX SUBJECT 273
SENSOR MATRIX VALUES
SENSOR ENROLL BOXPLOT
SENSOR TEST BOXPLOT
ACTION TYPE MATRIX
ACTION TYPE MATRIX VALUES
ACTION TYPE ENROLL BOXPLOT
ACTION TYPE TEST BOXPLOT
SENSOR TYPE MATRIX
SENSOR TYPE MATRIX VALUES
SENSOR TYPE ENROLL BOXPLOT
SENSOR TYPE TEST BOXPLOT
INTERACTION TYPE MATRIX
INTERACTION TYPE MATRIX VALUES
INTERACTION TYPE ENROLL BOXPLOT
INTERACTION TYPE TEST BOXPLOT
HISTOGRAM OF SSI BY ENROLLMENT
SENSOR
• Data is not normal
• Ran Kruskal-Wallis test
00
1
2
3
4
5
6
41.0- 00.0 41.0 82.0 24.0 65.0 07.0 48.
0.1760 0.1303 1440
0.2782 0.1788 1440
0.1691 0.1361 1440
0.1685 0.1320 1440
0.1896 0.1430 1440
0.1741 0.1410 1440
0.1802 0.1406 1440
0.2023 0.1499 1440
0.1634 0.1313 1440
Mean StDev N
S
ytisn
eD
IS
A
rosneS llornE
T KEPU
S KEPU
xitnedI
cinortuF
ustijuF
anosreP latigiD
hctaMssorC
cetnehtuA
lemt
N lamro
•H0= the median SSI scores are equal
•Ha= the median SSI scores are not equal
KRUSKAL-WALLIS TEST
Sensor H DF P
Atmel 58.80 8 0
Authentec 221.45 8 0
Crossmatch 63.75 8 0
Digital Persona 56.33 8 0
Fujitsu 121.45 8 0
Futronic 81.66 8 0
Identix 102.72 8 0
UPEK S 109.80 8 0
UPEK T 82.62 8 0
KRUSKAL-WALLIS RESULTS
•All p-values resulted in p=0
•Reject H0
• Meaning the medians of the SSIs across the
sensors are significantly different
KRUSKAL-WALLIS RESULTS
CONCLUSION
• Subjects are not stable across different sensors
using SSI
• Enrolling on Authentec produced the worst SSIs
overall, but testing on it did not show the same
pattern
• Predicting how unstable a user will be from
enrollment to testing would increase performance
CONCLUSION
•Look at stability across force levels
•See if type of sensor plays a role (thermal,
swipe, touch, etc.)
•Analyze the image quality of the images and
look for a relationship
FUTURE WORK