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tf.metrics.specificity_at_sensitivity(labels, predictions, sensitivity, weights=None, num_thresholds=200, metrics_collections=None, updates_collections=None, name=None)

tf.metrics.specificity_at_sensitivity(labels, predictions, sensitivity, weights=None, num_thresholds=200, metrics_collections=None, updates_collections=None, name=None)

Computes the specificity at a given sensitivity.

The specificity_at_sensitivity function creates four local variables, true_positives, true_negatives, false_positives and false_negatives that are used to compute the specificity at the given sensitivity value. The threshold for the given sensitivity value is computed and used to evaluate the corresponding specificity.

For estimation of the metric over a stream of data, the function creates an update_op operation that updates these variables and returns the specificity. update_op increments the true_positives, true_negatives, false_positives and false_negatives counts with the weight of each case found in the predictions and labels.

If weights is None, weights default to 1. Use weights of 0 to mask values.

For additional information about specificity and sensitivity, see the following: https://en.wikipedia.org/wiki/Sensitivity_and_specificity

Args:

  • labels: The ground truth values, a Tensor whose dimensions must match predictions. Will be cast to bool.
  • predictions: A floating point Tensor of arbitrary shape and whose values are in the range [0, 1].
  • sensitivity: A scalar value in range [0, 1].
  • weights: Optional Tensor whose rank is either 0, or the same rank as labels, and must be broadcastable to labels (i.e., all dimensions must be either 1, or the same as the corresponding labels dimension).
  • num_thresholds: The number of thresholds to use for matching the given sensitivity.
  • metrics_collections: An optional list of collections that specificity should be added to.
  • updates_collections: An optional list of collections that update_op should be added to.
  • name: An optional variable_scope name.

Returns:

  • specificity: A scalar Tensor representing the specificity at the given specificity value.
  • update_op: An operation that increments the true_positives, true_negatives, false_positives and false_negatives variables appropriately and whose value matches specificity.

Raises:

  • ValueError: If predictions and labels have mismatched shapes, if weights is not None and its shape doesn't match predictions, or if sensitivity is not between 0 and 1, or if either metrics_collections or updates_collections are not a list or tuple.

Defined in tensorflow/python/ops/metrics_impl.py.

© 2017 The TensorFlow Authors. All rights reserved.
Licensed under the Creative Commons Attribution License 3.0.
Code samples licensed under the Apache 2.0 License.
https://www.tensorflow.org/api_docs/python/tf/metrics/specificity_at_sensitivity