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| A neural network model of digit recognition |
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| The
top two layers form a |
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| restricted
Boltzmann machine |
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| whose
free energy landscape |
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| models
the low dimensional |
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| manifolds
of the digits. |
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| The
valleys have names: |
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| 2000 top-level units |
| 500 units |
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| The model learns
a joint density for |
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| labels and images. To
perform |
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| recognition we
can start with a neutral |
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| state of the
label units and do one or |
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| two iterations of
the top-level RBM. |
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| Or we can just
compute the free energy |
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| of the RBM with
each of the 10 labels |
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| 500 units |
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| 28 x 28 |
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| pixel |
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| image |
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