View source on GitHub |
Compute exponentially weighted moving {mean,variance} of a streaming value.
tf.contrib.distributions.moving_mean_variance(
value, decay, collections=None, name=None
)
The exponentially-weighting moving mean_var
and variance_var
are updated
by value
according to the following recurrence:
variance_var = decay * (variance_var + (1-decay) * (value - mean_var)**2)
mean_var = decay * mean_var + (1 - decay) * value
For derivation justification, see [Finch (2009; Eq. 143)][1].
Unlike assign_moving_mean_variance
, this function handles
variable creation.
Args | |
---|---|
value
|
float -like Tensor . Same shape as mean_var and variance_var .
|
decay
|
A float -like Tensor . The moving mean decay. Typically close to
1. , e.g., 0.999 .
|
collections
|
Python list of graph-collections keys to which the internal
variables mean_var and variance_var are added.
Default value is [GraphKeys.GLOBAL_VARIABLES] .
|
name
|
Optional name of the returned operation. |
Returns | |
---|---|
mean_var
|
Variable representing the value -updated exponentially weighted
moving mean.
|
variance_var
|
Variable representing the value -updated
exponentially weighted moving variance.
|
Raises | |
---|---|
TypeError
|
if value_var does not have float type dtype .
|
TypeError
|
if value , decay have different base_dtype .
|
References
[1]: Tony Finch. Incremental calculation of weighted mean and variance. Technical Report, 2009. http://people.ds.cam.ac.uk/fanf2/hermes/doc/antiforgery/stats.pdf