Fig. 6.

Distribution of the similarity indexes computed between experimental and predicted joint moments from all validation trials and subjects. Similarity indexes include the coefficient of determination (R²) and the root mean square error normalized to the root mean square sum of the experimental joint moments (RMSE). Histograms gather the R² and RMSE values in intervals with a 0.1-fixed-width in the (zero-to-1) range. In this range, vertical lines highlight a number of variables including the average indexes (i.e., mean) and those within one standard deviation (i.e., SD), the maximum expected RMSE and the minimum expected R² calculated using the Chebyshev's theorem assuming a 90% confidence interval (i.e., Chebyshev 90%), as well as the most unfavorable index values including R² = 0.58 (i.e., min R²) and RMSE = 0.704 (i.e., max RMSE).