.74 3.81 3.60 1.93 1.83 2.21 2.02 20.75 27.03 0.67 0.90 Mean 6.07 5.40 6.88 4.77 80.47 7.69 4.37 s11606-015-3271-0 2.32 3.68 2.57 2.20 25.75 33.01 0.82 0.96 Variance 6.01 3.12 5.75 4.34 194.70 81.75 3.24 0.87 1 0.71 0.28 124.64 174.96 0.11 0.02 Pr. max 0.16 0.22 0.24 0.18 0.03 0.05 0.24 0.46 0.34 0.52 0.72 0.04 0.04 1.38 2.73 Skew. -0.06 0.21 2.22 -0.19 -0.11 0.70 0.73 0.67 75.70 0.80 -0.16 1.06 1.22 1.06 0.37 Kurt. 2.71 2.84 13.65 2.75 2.72 3.75 3.81 3.65 39520.80 4.04 2.73 5.09 5.86 4.95 3.03 min. 1 1 4 1 12.31 -20.12 1 1 1 1 1 1.52 12.21 0.13 0.50 max. 12 10 12 9 120.12 40.32 1 4 7 5 3 80.23 78.12 2.30 1.50 MSE 4.12e-03 3.76e-03 6.78e-03 5.75e-03 4.84e-04 1.01e-03 3.29e-03 3.48e-02 1.55e-02 1.38e-02 4.10e-03 3.36e-04 4.21e-04 2.24e-02 6.99e-doi:10.1371/journal.pone.0123254.talso observed during the analyses of the Western and central Western signatures because their donors usually write the full name or larger names than the other style. However, it can be seen that the model of all the datasets is 5 to 6 letters per signature, independently of the number of lines and the styles. The parameters of the parametric GEV distribution can be seen at Table 3. Regarding the number of letters per word, we have differentiated the signatures written in one line (all databases) and the signatures written in two (DB1). Firstly, the non-parametric distribution for the signatures written in one line are shown according to the distribution of letters in the first word (Fig 5), the second (Fig 6) and the third one (Fig 7). It is observed that DB3 and DB4 are datasets whose maximum number of words is two. Once again, the Kolmogorov-Smirnov test determined the more suitable clustering representation for these feature in all databases. Secondly, the number of letters in signatures with two lines from DB1 is analyzed in Fig 8. The inferred densities present a bimodal behavior basically due to the presence of text based on names or surnames as initials whose probability is proportional to the number of words. When the first symbol is an upper case initial, 60.0 of the 4-Hydroxytamoxifen msds signers write a full-stop after such an initial. However, these signers do not keep such behavior constant. The probability that all of a signer’s signatures retain the full-stop jir.2013.0113 after the initial signing is estimated to be 73.0 . Similarly, the connectivity between letters in a word is not constant in signer behavior. We have found that, as an average, signers connect 59 of the characters in their signature.PLOS ONE | DOI:10.1371/journal.pone.0123254 April 10,11 /Modeling the Lexical Morphology of Western Handwritten SignaturesFig 5. buy 4-Hydroxytamoxifen Letter distribution in the first word for signatures written in one line. doi:10.1371/journal.pone.0123254.gFig 6. Letter distribution in the second word for signatures written in one line. doi:10.1371/journal.pone.0123254.gAdditionally, some people write their signatures with more rightward angle than their basic handwriting. Such an angle is called slant and it is measured in degrees. An example of how it is defined can be found in the eighth signature in Fig 1. Although the majority of text in the signatures appears fairly level, without a tilt, we perceive that there is a major tendency for rightslanted signature than left-slanted one, i.e., people tend to write in cursive style at a slight angle, away from the vertical, according to the estimated distribution in Fig 9. he statistical test estimated that the parametric distribution of slant is quite common in all databases..74 3.81 3.60 1.93 1.83 2.21 2.02 20.75 27.03 0.67 0.90 Mean 6.07 5.40 6.88 4.77 80.47 7.69 4.37 s11606-015-3271-0 2.32 3.68 2.57 2.20 25.75 33.01 0.82 0.96 Variance 6.01 3.12 5.75 4.34 194.70 81.75 3.24 0.87 1 0.71 0.28 124.64 174.96 0.11 0.02 Pr. max 0.16 0.22 0.24 0.18 0.03 0.05 0.24 0.46 0.34 0.52 0.72 0.04 0.04 1.38 2.73 Skew. -0.06 0.21 2.22 -0.19 -0.11 0.70 0.73 0.67 75.70 0.80 -0.16 1.06 1.22 1.06 0.37 Kurt. 2.71 2.84 13.65 2.75 2.72 3.75 3.81 3.65 39520.80 4.04 2.73 5.09 5.86 4.95 3.03 min. 1 1 4 1 12.31 -20.12 1 1 1 1 1 1.52 12.21 0.13 0.50 max. 12 10 12 9 120.12 40.32 1 4 7 5 3 80.23 78.12 2.30 1.50 MSE 4.12e-03 3.76e-03 6.78e-03 5.75e-03 4.84e-04 1.01e-03 3.29e-03 3.48e-02 1.55e-02 1.38e-02 4.10e-03 3.36e-04 4.21e-04 2.24e-02 6.99e-doi:10.1371/journal.pone.0123254.talso observed during the analyses of the Western and central Western signatures because their donors usually write the full name or larger names than the other style. However, it can be seen that the model of all the datasets is 5 to 6 letters per signature, independently of the number of lines and the styles. The parameters of the parametric GEV distribution can be seen at Table 3. Regarding the number of letters per word, we have differentiated the signatures written in one line (all databases) and the signatures written in two (DB1). Firstly, the non-parametric distribution for the signatures written in one line are shown according to the distribution of letters in the first word (Fig 5), the second (Fig 6) and the third one (Fig 7). It is observed that DB3 and DB4 are datasets whose maximum number of words is two. Once again, the Kolmogorov-Smirnov test determined the more suitable clustering representation for these feature in all databases. Secondly, the number of letters in signatures with two lines from DB1 is analyzed in Fig 8. The inferred densities present a bimodal behavior basically due to the presence of text based on names or surnames as initials whose probability is proportional to the number of words. When the first symbol is an upper case initial, 60.0 of the signers write a full-stop after such an initial. However, these signers do not keep such behavior constant. The probability that all of a signer’s signatures retain the full-stop jir.2013.0113 after the initial signing is estimated to be 73.0 . Similarly, the connectivity between letters in a word is not constant in signer behavior. We have found that, as an average, signers connect 59 of the characters in their signature.PLOS ONE | DOI:10.1371/journal.pone.0123254 April 10,11 /Modeling the Lexical Morphology of Western Handwritten SignaturesFig 5. Letter distribution in the first word for signatures written in one line. doi:10.1371/journal.pone.0123254.gFig 6. Letter distribution in the second word for signatures written in one line. doi:10.1371/journal.pone.0123254.gAdditionally, some people write their signatures with more rightward angle than their basic handwriting. Such an angle is called slant and it is measured in degrees. An example of how it is defined can be found in the eighth signature in Fig 1. Although the majority of text in the signatures appears fairly level, without a tilt, we perceive that there is a major tendency for rightslanted signature than left-slanted one, i.e., people tend to write in cursive style at a slight angle, away from the vertical, according to the estimated distribution in Fig 9. he statistical test estimated that the parametric distribution of slant is quite common in all databases.