A Prototype of Mathematical Treatment of Pen Pressure Data for Signature Verification

• Published in: Journal of forensic sciences 2018-01, Vol.63 (1), p.275-284
• Main Authors: Li, Chi‐Keung, Wong, Siu‐Kay, Chim, Lai‐Chu Joyce
• Format: Article
• Language: English
• Subjects: Correlation coefficients; documents examination; forensic science; Forensic sciences; Matching; Mathematical analysis; pearson's correlation coefficient; pen pressure pattern; prototype; signature identification; Signatures
• ISSN: 0022-1198; 1556-4029
• DOI: 10.1111/1556-4029.13491

A prototype using simple mathematical treatment of the pen pressure data recorded by a digital pen movement recording device was derived. In this study, a total of 48 sets of signature and initial specimens were collected. Pearson's correlation coefficient was used to compare the data of the pen pressure patterns. From the 820 pair comparisons of the 48 sets of genuine signatures, a high degree of matching was found in which 95.4% (782 pairs) and 80% (656 pairs) had rPA > 0.7 and rPA > 0.8, respectively. In the comparison of the 23 forged signatures with their corresponding control signatures, 20 of them (89.2% of pairs) had rPA values < 0.6, showing a lower degree of matching when compared with the results of the genuine signatures. The prototype could be used as a complementary technique to improve the objectivity of signature examination and also has a good potential to be developed as a tool for automated signature identification.