4.3.3. Results on Medium PE Category

Figure 16 and Table 5 display system performance on persons belonging to the category of medium PE. The obtained results on this category show an intermediate behavior compared to that observed on high and low PE categories. More precisely, the initials are the worst type in terms of performance.

**Figure 16.** System performance on users of the medium PE category considering the 8 signature types.


**Table 5.** System performance on users of the medium PE category in terms of EER.

Moreover, the DET-curves corresponding to name-surname and usual signature types intersect at the EER value and get closer compared to problematic users. Also, the hybrid types including alphanumeric and handwriting information enhance significantly verification performance in uncontrolled mobile conditions. The SDP type in particular leads to a significant relative improvement of 93% at the EER compared to the usual signature; besides we note that the FAR and FRR are both bounded at 1.2% and 2%, respectively.
