Figure 4.

Estimated components of model (9) with ±2 pointwise standard errors. Coefficient surfaces are color-coded for sign and approximate pointwise significance (95%): blue if sig. < 0, light blue if < 0, light red if > 0, red if sig. > 0. Left to right: mean FA-CCA for healthy (blue, dotted) versus MS (red, solid) females; mean FA-CCA for female (purple, solid) and male (green, dotted) MS patients; estimated smooth index-varying age effect $\widehat{\nu }(u,t)$.