Table 3.
Overall classification performance (accuracy, in %) for k-Nearest Neighbors (kNN) algorithms, as a factor of different kernel functions, window lengths and percentage of window overlap.
Overlap [%] | Overlap [%] | Overlap [%] | ||||||||
---|---|---|---|---|---|---|---|---|---|---|
0 | 10 | 20 | 0 | 10 | 20 | 0 | 10 | 20 | ||
Fine Class | Medium Class | Coarse Class | ||||||||
Window [ms] | 300 | 96.4 | 96.4 | 96.7 | 96.3 | 96.0 | 96.5 | 89.2 | 89.8 | 90.6 |
400 | 96.3 | 96.3 | 97.0 | 96.1 | 96.5 | 96.8 | 90.1 | 90.5 | ||
500 | 96.1 | 97.0 | 97.0 | 96.0 | 96.5 | 96.1 | 89.7 | 89.8 | 90.4 | |
600 | 96.2 | 96.7 | 95.7 | 96.4 | 96.2 | 89.9 | 90.5 | |||
Cosine | Cubic | Weighted | ||||||||
Window [ms] | 300 | 96.4 | 96.3 | 96.6 | 94.0 | 93.7 | 94.1 | 96.4 | 96.3 | 96.8 |
400 | 96.3 | 96.5 | 96.5 | 93.9 | 94.2 | 94.9 | 96.4 | 96.7 | 96.9 | |
500 | 96.1 | 96.7 | 96.3 | 94.6 | 94.7 | 94.8 | 96.3 | 96.6 | 96.4 | |
600 | 96.1 | 96.5 | 94.7 | 94.9 | 94.8 | 96.3 | 96.9 | 96.5 |
Data from all the five IMUs available were used as input. Green bold numbers = best performance; red bold numbers = worst performance.