“…In particular, in [ 37 ], it has been observed that prequential coding yields much better codelengths than variational inference, correlating better with the test set performance — we remind that in the prequential coding, a model with default values is used to encode the first few data; then, the model is trained on these few encoded data; the partially trained model is used to encode the next data; then, the model is retrained on all data encoded so far, and so on. On the contrary, in [ 38 ], an MDL-based strategy is used for determining a parameter-free stopping criterion for semi-supervised learning in time series classification, while in [ 39 ], the problem of model change tracking and detection has been addressed and studied in both data-compression and hypothesis-testing scenarios. In the first case, an upper bound for the minimax regret for model changes has been found; in the second one, error probabilities for the MDL change test have been derived, and they rely on the information-theoretic complexity, i.e., the complexity of the model class or the model itself and the -divergence.…”