Can anyone give me the formula for weighted NLL. I want to know where weights are getting multiplied. I have read this https://pytorch.org/docs/stable/generated/torch.nn.NLLLoss.html but I am not able to understand what $x_{n,y_n}$
is basically. I want to write the formula for weight NLL for C classes. Is the following correct (consider I have correct labels and incorrect labels):

x
corresponds to the logits given as the model output.
Here is a comparison between a manual approach and the weighted criterion.
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Hi. Thanks for the answer. Can you please tell me whether the formula I have written above for reduction==‘mean’ is correct or not?
I don’t know how y
and y'
are defined, e.g. is y
a one-hot encoded target tensor acting as a mask (so alternatively also indexing would work using the class indices directly)?
If so, I guess the class index in w
would be missing but you could also compare it to the used formula in nn.CrossEntropyLoss
to make sure it’s equivalent.