tf.contrib.distributions.normal_conjugates_known_scale_posterior
Posterior Normal distribution with conjugate prior on the mean.
tf.contrib.distributions.normal_conjugates_known_scale_posterior( prior, scale, s, n )
This model assumes that n
observations (with sum s
) come from a Normal with unknown mean loc
(described by the Normal prior
) and known variance scale**2
. The "known scale posterior" is the distribution of the unknown loc
.
Accepts a prior Normal distribution object, having parameters loc0
and scale0
, as well as known scale
values of the predictive distribution(s) (also assumed Normal), and statistical estimates s
(the sum(s) of the observations) and n
(the number(s) of observations).
Returns a posterior (also Normal) distribution object, with parameters (loc', scale'**2)
, where:
mu ~ N(mu', sigma'**2) sigma'**2 = 1/(1/sigma0**2 + n/sigma**2), mu' = (mu0/sigma0**2 + s/sigma**2) * sigma'**2.
Distribution parameters from prior
, as well as scale
, s
, and n
. will broadcast in the case of multidimensional sets of parameters.
Args | |
---|---|
prior | Normal object of type dtype : the prior distribution having parameters (loc0, scale0) . |
scale | tensor of type dtype , taking values scale > 0 . The known stddev parameter(s). |
s | Tensor of type dtype . The sum(s) of observations. |
n | Tensor of type int . The number(s) of observations. |
Returns | |
---|---|
A new Normal posterior distribution object for the unknown observation mean loc . |
Raises | |
---|---|
TypeError | if dtype of s does not match dtype , or prior is not a Normal object. |
© 2020 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/versions/r1.15/api_docs/python/tf/contrib/distributions/normal_conjugates_known_scale_posterior