Fig. 3
Feature selection. (A) Features’ rank based on Kruskal-Wallis supervised feature selection test. (B) The features’ cross-correlation results. (C–F) compare the pairs of candidate features in terms of (C) linear regression \(R^2\), (D) healthy-patient classification rate, (E) affected-unaffected leg classification rate, and (F) severity grades classification rate. In addition, (G–J) illustrate the average profiles of the gait parameters for selected features of healthy individuals and pre-surgery affected leg of patients in different severity grades; (G) shows the area of gait path (F5), (H) depicts the hip maximum angular velocity (F6), (I) illustrates the area of path speed (F10). and (J) shows the area of hip limit cycle (F11).
