 |
|
|
|
|
|
|
|
|
|
|
|
|
|
| • |
Replace the top
layer of the causal network by an RBM
|
|
|
|
– |
This
eliminates explaining away at the top-level.
|
|
|
|
– |
It
is nice to have an associative memory at the top.
|
|
|
| • |
Replace the
sleep phase by a top-down pass starting with
|
|
the state of the
RBM produced by the wake phase.
|
|
|
|
– |
This
makes sure the recognition weights are trained in
|
|
|
the
vicinity of the data.
|
|
|
|
– |
It
also reduces mode averaging. If the recognition
|
|
|
weights
prefer one mode, they will stick with that mode
|
|
|
even
if the generative weights like some other mode
|
|
|
just
as much.
|
|