Plot Cross-Validation Results vs Eta
cv.plot.RdPlots cross-validation performance across eta values for
cv.coxkl, cv.coxkl_ridge, cv.coxkl_enet,
cv.cox_MDTL, cv.cox_MDTL_ridge, cv.cox_MDTL_enet,
cv.ncckl, cv.ncckl_enet, or cv.cox_indi_enet
objects in a Biometrics-style figure. It displays the cross-validated
performance curve (each eta at its best lambda), a baseline reference at
eta = 0, and marks the optimal eta.