mxnet-commits mailing list archives

Site index · List index
Message view « Date » · « Thread »
Top « Date » · « Thread »
From GitBox <...@apache.org>
Subject [GitHub] anirudhacharya commented on a change in pull request #12697: [MXNET -1004] Poisson NegativeLog Likelihood loss
Date Tue, 09 Oct 2018 01:10:52 GMT
anirudhacharya commented on a change in pull request #12697: [MXNET -1004] Poisson NegativeLog
Likelihood loss
URL: https://github.com/apache/incubator-mxnet/pull/12697#discussion_r223536222
 
 

 ##########
 File path: python/mxnet/gluon/loss.py
 ##########
 @@ -706,3 +707,65 @@ def hybrid_forward(self, F, pred, positive, negative):
                      axis=self._batch_axis, exclude=True)
         loss = F.relu(loss + self._margin)
         return _apply_weighting(F, loss, self._weight, None)
+
+
+class PoissonNLLLoss(Loss):
+    r"""For a target (Random Variable) in a Poisson distribution, the function calculates
the Negative
+    Log likelihood loss.
+    PoissonNLLLoss measures the loss accrued from a poisson regression prediction made by
the model.
+
+    .. math::
+        L = \text{pred} - \text{target} * \log(\text{pred}) +\log(\text{target!})
+
+    `pred`, `target` can have arbitrary shape as long as they have the same number of elements.
+
+    Parameters
+    ----------
+    from_logits : boolean, default True
+        indicating whether log(predicted) value has already been computed. If True, the loss
is computed as
+        :math:`\exp(\text{pred}) - \text{target} * \text{pred}`, and if False, then loss
is computed as
+        :math:`\text{pred} - \text{target} * \log(\text{pred}+\text{epsislon})`.The default
value
 
 Review comment:
   these definitions seem to be at odds with the definition given above in line 718

----------------------------------------------------------------
This is an automated message from the Apache Git Service.
To respond to the message, please log on GitHub and use the
URL above to go to the specific comment.
 
For queries about this service, please contact Infrastructure at:
users@infra.apache.org


With regards,
Apache Git Services

Mime
View raw message