Figure 4

Comparison between the methods RPD, FFT and LSP for series ectopically distorted ±15%. Results of linear regression log(Y) = p1∙log(X) + p0 between log transformed LF/HF ratios for IBI series with beats ectopically distorted with a strength of precisely ±15% (Y) compared to undistorted series (X) for the RPD, FFT and LSP methods (distortion rates up to 20%). Top: goodness of fit R²; Middle: coefficient p1; Bottom: intercept p0.