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Diffstat (limited to 'tensorflow/python/ops/nn_impl.py')
| -rw-r--r-- | tensorflow/python/ops/nn_impl.py | 5 |
1 files changed, 4 insertions, 1 deletions
diff --git a/tensorflow/python/ops/nn_impl.py b/tensorflow/python/ops/nn_impl.py index 67eee1c29e..837ee02e64 100644 --- a/tensorflow/python/ops/nn_impl.py +++ b/tensorflow/python/ops/nn_impl.py @@ -196,7 +196,10 @@ def weighted_cross_entropy_with_logits(targets, logits, pos_weight, name=None): targets * -log(sigmoid(logits)) + (1 - targets) * -log(1 - sigmoid(logits)) - The argument `pos_weight` is used as a multiplier for the positive targets: + A value `pos_weights > 1` decreases the false negative count, hence increasing the recall. + Conversely setting `pos_weights < 1` decreases the false positive count and increases the precision. + This can be seen from the fact that `pos_weight` is introduced as a multiplicative coefficient for the positive targets term + in the loss expression: targets * -log(sigmoid(logits)) * pos_weight + (1 - targets) * -log(1 - sigmoid(logits)) |