Exploring the significance of pen lifts as predictors of signature simulation behaviour

Historically, pen lifts have been considered valuable predictors of simulation behaviour. Despite this belief, there exists only limited empirical data available to characterise the extent to which unexpected pen lifts contribute to evidence in support of simulation behaviour. This study was devised to examine the frequency with which pen-lifts are observed in a population of 2280 simulated signatures as compared to a genuine signature population of 285 signatures (by 19 authors). It was found that 12% of simulated signatures featured less pen-lifts than their comparison genuine signatures, whilst 22% of simulated signatures featured more pen lifts than their genuine counterparts. The variance in pen lift incidence in the simulated signatures, as compared to the known model signatures, was found to be non-significant for both over and under representation of lifts. Sixty-seven percent of the simulations were found to successfully replicate both the number and placement of the pen lifts, when compared to their respective models. Despite the lack of statistical significance, 33% of simulations were observed to have more or less pen lifts then their genuine model counterparts and should be explored further. The results gained provide an insight into the significance of pen lifts with respect to whether or not they appear in a questioned signature, and whether the occurrence of pen lifts in questioned signatures independently provides evidence of simulated writing behaviour.