Figure 19.

Schematic drawing of error rates changing along with drift extent and drift rate increasing. (a) Error rate changing along with drift extent increasing for complete adaption and incomplete adaption; (b) Error rate changing along with drift rate increasing, under the condition of fixed maximum drift extent. The plots of complete adaption and incomplete adaption in (a) are simplified from Figure 10. The plots in (b) are simplified from Figure 13. There are critical drift rates for adaptive classifiers, noted as DRT_uISVC, DRT_uPAC, DRT_sPAC, DRT_sISVC respectively. When drift rate is smaller than the critical drift rate, the classifier can achieve complete adaption and keep the error rate low, when drift rate is larger than the critical drift rate, the adaption is incomplete adaption and the error rate increase dramatically along with drift rate increasing. (① the possible average drift rate of realistic data from one-day-long EMG acquiring trials).