Figure 2.

Contour plots of the mean prediction errors of DOSK for Regression Example 2 where p₀ = 8. Here λ₃ is set as {0, 0.25, 0.5, 1} for the four panels and the kernel bandwidth $\tau =1/2{\widehat{\sigma }}^2$, where $\widehat{\sigma }$ is the median of the pairwise Euclidean distances of the simulated samples.