A COMPARISON AND EVALUATION OF MOTION INDEXING ...

Figure 5.12: False Positives detected by each Technique.
The two PCA-based have the lowest number of false negatives but at the same
time have large number of false positives (close to 90%) which shows that these two
techniques incorrectly classify non-matches as matches. The feature-based and DTW
quaternion-based techniques perform better than the PCA-based techniques. They
have almost similar results with DTW-Quat performing a little better because both
these techniques are very sensitive to small differences in joint configurations. DTW-
3D has the best performance among all the five techniques because although it has a
small number of false positives, the false negatives are also very less.
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