Gaussian Processes (GPs) are useful for modeling uncertainty with function-space priors, while Bayesian Neural Networks (BNNs) are more scalable but lack some GP advantages.
Efforts have been made to make BNNs behave like GPs, but previous solutions have limitations.
A study shows that using trainable activations is essential to map GP priors effectively to wide BNNs.
The closed-form 2-Wasserstein distance is used for efficient optimization of reparameterized priors and activations.
The method introduces trainable periodic activations for global stationarity and functional priors conditioned on GP hyperparameters for efficient model selection.
Empirical results demonstrate that the proposed method outperforms existing approaches and matches heuristic methods with stronger theoretical foundations.