tf.contrib.metrics.precision_recall_at_equal_thresholds

A helper method for creating metrics related to precision-recall curves.

tf.contrib.metrics.precision_recall_at_equal_thresholds(
    labels, predictions, weights=None, num_thresholds=None, use_locking=None,
    name=None
)

These values are true positives, false negatives, true negatives, false positives, precision, and recall. This function returns a data structure that contains ops within it.

Unlike _streaming_confusion_matrix_at_thresholds (which exhibits O(T * N) space and run time), this op exhibits O(T + N) space and run time, where T is the number of thresholds and N is the size of the predictions tensor. Hence, it may be advantageous to use this function when predictions is big.

For instance, prefer this method for per-pixel classification tasks, for which the predictions tensor may be very large.

Each number in predictions, a float in [0, 1], is compared with its corresponding label in labels, and counts as a single tp/fp/tn/fn value at each threshold. This is then multiplied with weights which can be used to reweight certain values, or more commonly used for masking values.

Args
labels	A bool Tensor whose shape matches predictions.
predictions	A floating point Tensor of arbitrary shape and whose values are in the range [0, 1].
weights	Optional; If provided, a Tensor that has the same dtype as, and broadcastable to, predictions. This tensor is multiplied by counts.
num_thresholds	Optional; Number of thresholds, evenly distributed in [0, 1]. Should be >= 2. Defaults to 201. Note that the number of bins is 1 less than num_thresholds. Using an even num_thresholds value instead of an odd one may yield unfriendly edges for bins.
use_locking	Optional; If True, the op will be protected by a lock. Otherwise, the behavior is undefined, but may exhibit less contention. Defaults to True.
name	Optional; variable_scope name. If not provided, the string 'precision_recall_at_equal_threshold' is used.

Returns
result	A named tuple (See PrecisionRecallData within the implementation of this function) with properties that are variables of shape [num_thresholds]. The names of the properties are tp, fp, tn, fn, precision, recall, thresholds. Types are same as that of predictions.
update_op	An op that accumulates values.

Raises
ValueError	If predictions and labels have mismatched shapes, or if weights is not None and its shape doesn't match predictions, or if includes contains invalid keys.