Fig. 7. An example of PD, ICE and interaction detection for simulated data.

The (A) PD and (B) ICE plot for x₀. The simulated data have the form $f(x)=x_0^2+0.1{\sum }_{i=1}^{N-1}{x}_i+\mathrm{ϵ}$, where x is drawn from a uniform probability distribution between −1 and 1 and ϵ ∼ N(0,0.25). The $x_0^2$ relationship can be seen in the PD. The dashed lines show the 95% confidence interval, and the solid line is the mean value for the five models fit. An NN model is used. The PD plot it centered so that PD(0) = 0 for the mean of the ensemble. The ICE plot is centered so that $\widehat{f}(0,x_c^{(i)})=0$. (C) The distribution of H statistics for the real ensemble model and null distribution for an NN ensemble model fit to f(x) = x₀ + x₁ + x₀x₁ + ϵ.