The type of the inputs to addmm_ should be both FloatTensor or DoubleTensor.
What’s the type of word_embedding.embeddings in nn.Parameter(word_embedding.embeddings, requires_grad=False)? It seems that you pass a word_embedding of type DoubleTensor to DecomposableModel’s __init__ anywhere else in the code (I guess it’s in your trainer.py 23). Make it to FloatTensor.