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I'm trying to get grasp of Bayes regularization algorithm. List of symbols 1st:
$F$ - objective function
$\gamma$ - regularization parameter
$M$ - number od neural network weights
$N$ - number of data tuples
$e$ - modeling error
$w$ - net weight
$D$ - data set input-output pair
$H$ - Hess matrix of objective function computed based on Jacoby's matrix

I get it that minimalising an objective function: $$ F = \gamma\sum\limits _{j=1} ^Mw_j^2 + (1-\gamma)\sum\limits_{i=1}^Ne_i^2 $$ is equivalent to maximising likelihood $P(w|D,\gamma)$, which can be computed according to Bayes' theorem: $$ P(w|D,\gamma) = \frac{P(D|w,\gamma)P(w|\gamma)}{P(D|\gamma)} $$ Likelihood $P(w|\gamma)$ is assumed to be a gaussian one and can be computed as: $$ P(w|\gamma)=\left(\frac{\gamma}{2N}\right)^{\frac{M}{2}}\cdot e^{-\frac{\gamma}{2}w^Tw} $$ Likelihood $P(D|\gamma)$ can be computed too as: $$ P(D|\gamma)=\left(\frac{\pi}{\gamma}\right)^{-\frac{N}{2}}\left(\frac{\pi}{1-\gamma}\right)^{-\frac{M}{2}}\frac{(2\pi)^\frac{M}{2}\cdot -e^{-F(w)}}{\sqrt{|H|}} $$ And now my questions are: how is $P(D|w,\gamma)$ computed? Or maybe is there any special assumptions about it? And should I minimalise or maximise $P(w|D,\gamma)$ to minimalise objective function $F$.
I base on those articles: Article1 Article2

If anyone is able to explain those thing to me, I'd be most grateful.
Thank you,
Max

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1 Answer 1

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I have found answer for my question here.

If anyone needs it in future: all above likelihoods are assumed to be a gaussian distributions. Likelihood $P(\gamma)$ is assumed to be uniform. In the article it is shown how exactly are they defined and how to compute further is described in detail in article linked above.

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