The applied five ML methods, three of which are tree-based and two are NN-based, performed well on the Test-1 instances as the Test-1 scores were close to the Training scores. However, tree-based models had a significant performance drop when extrapolating on the Test-2 domain compared to NN-based models. This result shows that NN-based models are much more robust on extrapolation than tree-based models. We also compared the effect of different encoding methods (see Table ).