where yk represents the predicted response (e.g., IPC) of the k-th configuration (k =
1, . . . , N), and ˆyk represents the actual response of the k-th configuration, which is
obtained by cycle-by-cycle simulation. To compare the prediction accuracy of COAL
with that of the state-of-the-art (ANN), the MSE of COAL on the testing data will be
normalized to that of the ANN DSE approach introduced by ¨Ipek et al. [2006].