Please refer to the paper by Zhou et al. for more details on these hyperparameters. According to suggestions by the authors, we increase the model size, i.e., "hidden_size", "unroll_length", and "num_epochs" of the pretraining for problem domains with more than three input variables (here "num_params"), since the problem becomes exponentially harder as the number of input variables increases. Therefore, significantly higher computational capacities are required, leading to a longer pre-training time.