Computes the precision of the predictions with respect to the labels
metric_precision(
...,
thresholds = NULL,
top_k = NULL,
class_id = NULL,
name = NULL,
dtype = NULL
)
A (subclassed) Metric
instance that can be passed directly to
compile(metrics = )
, or used as a standalone object. See ?Metric
for
example usage.
Passed on to the underlying metric. Used for forwards and backwards compatibility.
(Optional) A float value or a list of float
threshold values in [0, 1]
. A threshold is compared with prediction values
to determine the truth value of predictions (i.e., above the threshold is
true
, below is false
). One metric value is generated for each threshold
value. If neither thresholds nor top_k are set, the default is to calculate
precision with thresholds=0.5
.
(Optional) Unset by default. An int value specifying the top-k predictions to consider when calculating precision.
(Optional) Integer class ID for which we want binary metrics.
This must be in the half-open interval [0, num_classes)
, where
num_classes
is the last dimension of predictions.
(Optional) string name of the metric instance.
(Optional) data type of the metric result.
The metric creates two local variables, true_positives
and
false_positives
that are used to compute the precision. This value is
ultimately returned as precision
, an idempotent operation that simply
divides true_positives
by the sum of true_positives
and
false_positives
.
If sample_weight
is NULL
, weights default to 1. Use sample_weight
of 0
to mask values.
If top_k
is set, we'll calculate precision as how often on average a class
among the top-k classes with the highest predicted values of a batch entry is
correct and can be found in the label for that entry.
If class_id
is specified, we calculate precision by considering only the
entries in the batch for which class_id
is above the threshold and/or in
the top-k highest predictions, and computing the fraction of them for which
class_id
is indeed a correct label.
Other metrics:
custom_metric()
,
metric_accuracy()
,
metric_auc()
,
metric_binary_accuracy()
,
metric_binary_crossentropy()
,
metric_categorical_accuracy()
,
metric_categorical_crossentropy()
,
metric_categorical_hinge()
,
metric_cosine_similarity()
,
metric_false_negatives()
,
metric_false_positives()
,
metric_hinge()
,
metric_kullback_leibler_divergence()
,
metric_logcosh_error()
,
metric_mean_absolute_error()
,
metric_mean_absolute_percentage_error()
,
metric_mean_iou()
,
metric_mean_relative_error()
,
metric_mean_squared_error()
,
metric_mean_squared_logarithmic_error()
,
metric_mean_tensor()
,
metric_mean_wrapper()
,
metric_mean()
,
metric_poisson()
,
metric_precision_at_recall()
,
metric_recall_at_precision()
,
metric_recall()
,
metric_root_mean_squared_error()
,
metric_sensitivity_at_specificity()
,
metric_sparse_categorical_accuracy()
,
metric_sparse_categorical_crossentropy()
,
metric_sparse_top_k_categorical_accuracy()
,
metric_specificity_at_sensitivity()
,
metric_squared_hinge()
,
metric_sum()
,
metric_top_k_categorical_accuracy()
,
metric_true_negatives()
,
metric_true_positives()