Optimal-er Auctions through Attention

RegretNet is a recent breakthrough in the automated design of revenue-maximizing auctions. It combines the expressivity of deep learning with the regret-based approach to relax and quantify the Incentive Compatibility constraint (that participants benefit from bidding truthfully). We propose two independent modifications of RegretNet, namely a new neural architecture based on the attention mechanism, denoted as RegretFormer, and an alternative loss function that is interpretable and significantly less sensitive to hyperparameters. We investigate both proposed modifications in an extensive experimental study in settings with fixed and varied input sizes and additionally test out-of-setting generalization of our network. In all experiments, we find that RegretFormer consistently outperforms existing architectures in revenue. Regarding our loss modification, we confirm its effectiveness at controlling the revenue-regret trade-off by varying a single interpretable hyperparameter.