Research Information System
12th Annual Scientific Meeting Balkan Academy of Forensic Sciences , İstanbul, Turkey, 24 - 26 September 2021, pp.34-35, (Summary Text)
This study was carried out to determine the changes in signatures over time. Signature is a biometric element consisting of descriptive texts and figures that shows an individual's characteristics. The signature, like handwriting, undergoes some changes over time. These changes may occur due to personal and environmental factors. In order to define such changes, a sample group including ten participants was determined and their signatures on timesheets for 1st, 7th, 15th, 30th, 90th, 180th and 360th days were examined. It is expected that some changes may occur in second signatures which are signed at the end of the working day. These signatures were evaluated in terms of "complexity", "speed", "pressure", "deviation angle from the baseline", "aspect ratio" and "special marks" variables. When the change in signature characteristics in different time period were examined; it was observed that "speed" has decreased while "pressure" has increased (%40) or both have remained constant (%50) for most of the participants. While the "complexity" (%70) and "deviation angle from the baseline" (%90) of the signatures remained constant, "aspect ratio" of signatures in half of the participants tended to remain constant (%50). When the change of the second signature on the same day is also examined, it was observed that the second signatures of four participants had more pressure whereas two participants had less pressure; three participants had a tendency to exaggerate the initial stroke of their signatures; four participants had a tendency to decrease the number of mid characters, six participants had changes in their last figure of their signatures and four participants had similar characters in comparison with first signatures. At the end of the working day, as an expected result of acting in a hurry to catch the shuttle service, an increase in speed and a decrease in pressure were observed in the signature of only one participant. This study is a preliminary study for more comprehensive studies that are carried out by expanding the sample group and evaluating many factors such as age, gender and professions together.
Key Words: signature, variation, handwriting and signature examination, document examination, forensic science.