Using complementary priors to eliminate
explaining away
A “complementary” prior is defined
as one that exactly cancels the
correlations created by explaining
away. So the posterior factors.
Under what conditions do
complementary priors exist?
Is there a simple way to
compute the product of the
likelihood term and the prior
term from the data?
Yes!  In one kind of sigmoid
belief net, we can simply use
hidden variables
hidden variables
prior
hidden variables
likelihood
          data