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    | How to compress document count vectors 
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    | 2000 
    reconstructed counts 
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    | • | We train the 
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    |  | autoencoder to 
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    |  | reproduce its
    input 
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    |  | vector as its
    output 
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    | • | This forces it to 
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    |  | compress as much 
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    |  | information as
    possible 
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    |  | into the 2 real
    numbers 
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    |  | in the central
    bottleneck. 
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    | • | These 2 numbers
    are 
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    |  | then a good way
    to 
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    |  | visualize
    documents. 
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    | Input
    vector uses 
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    | Poisson
    units 
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