Hi, thanks for your response.
Interestingly, I get the old BatchNorm answer from Python (I have torch.__version__ = 1.1.0, you’re probably using a more recent version).
This indicates that both Python and libtorch changed behavior recently. A simple math shows that the results of the new BatchNorm2d are actually correct. What I would like to understand, though, is what changed between these two. If I know what the old implementation did, hopefully I can understand why my model converged there, but not anymore.