Difference between revisions of "Thread:Talk:Rolling Averages/Rolling Average vs Softmax & Cross Entropy"

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: q<sub>i</sub>, otherwise
 
: q<sub>i</sub>, otherwise
  
If gradient is not applied on logit as normal, but instead applied on q<sub>i</sub> itself, then:
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If gradient is not applied on logits as normal, but instead applied on q<sub>i</sub> itself, then:
 
: q<sub>i</sub> := q<sub>i</sub> - eta * (q<sub>i</sub> - 1) = (1 - eta) * q<sub>i</sub> + eta * 1, if bin i hit
 
: q<sub>i</sub> := q<sub>i</sub> - eta * (q<sub>i</sub> - 1) = (1 - eta) * q<sub>i</sub> + eta * 1, if bin i hit
 
: q<sub>i</sub> := q<sub>i</sub> - eta * q<sub>i</sub> = (1 - eta) * q<sub>i</sub> + eta * 0, otherwise
 
: q<sub>i</sub> := q<sub>i</sub> - eta * q<sub>i</sub> = (1 - eta) * q<sub>i</sub> + eta * 0, otherwise
 
Which is essentially rolling average, where eta (learning rate) equals to the alpha (decay rate) in exponential moving average.
 
Which is essentially rolling average, where eta (learning rate) equals to the alpha (decay rate) in exponential moving average.
  
Anyway this analog isn't how rolling average works, as logit isn't q<sub>i</sub> actually. But what if we replace rolling average with gradient descent? I suppose it could learn even faster, as the outputs far from real value get higher decay rate...
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Anyway this analog isn't how rolling average works, as logit doesn't equal to q<sub>i</sub> at all. But what if we replace rolling average with gradient descent? I suppose it could learn even faster, as the outputs farther from real value get higher decay rate...

Revision as of 05:58, 27 July 2021

If each Guess Factor bin is considered an output unit before Softmax (logit), and loss is Cross Entropy, then the gradient of each logit is then:

qi - 1, if bin is hit
qi, otherwise

If gradient is not applied on logits as normal, but instead applied on qi itself, then:

qi := qi - eta * (qi - 1) = (1 - eta) * qi + eta * 1, if bin i hit
qi := qi - eta * qi = (1 - eta) * qi + eta * 0, otherwise

Which is essentially rolling average, where eta (learning rate) equals to the alpha (decay rate) in exponential moving average.

Anyway this analog isn't how rolling average works, as logit doesn't equal to qi at all. But what if we replace rolling average with gradient descent? I suppose it could learn even faster, as the outputs farther from real value get higher decay rate...