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Bayesian Methods in Machine
          Learning
         Mohammad Shazri
       mshazri@gmail.com
   shazri.shahrir@extolcorp.com
Sources
 Papers from Michael Tipping
  -Bayesian Inference: An introduction to Principles in Machine Learning
 Youtube from mathematicalmonk
approximate P(B|A)

 P(B|A)=f(A;w) .. A is the exemplars and w is
  the weights.|given A, what is B?.
 B and A usually relates as D= {A_n,B_n} from
  n=1 to N.
 Prior statements, possible to over-fit.
Initial statement
 Given A , what is the likelihood of B.
 P(B|A)
 Then to approximate P(B|A)
Setup and Model
 Setup; it is a supervised learning situation
 (1) Models/Basis* shape are normally
  distributed
 (2) confidence weights/tuneVar are
  independent.
 (3) there are precision tuners on
  basis+weights. Var and alpha
 (4) all are known except weights.
Usual vs MAP
 Usual ; over-fitting
 MAP ; solves over-fitting but there is no
  interpretation of BR.
______________________________________
 Confidence-Level/Interpretation of the
  unknown
Complexity Control : Regularization
 E(w)= E_d(w)+lambda*E_w(w)
 E_d is the standard regression
  model, liner, sigmoid etc.
 E_w is the penalty
 Lamda is a hyperparameter
Error model




-Note there is no x
Log of error model
Tune Shape




Confidence on w
+
shape of error contribution
Interpretation
Lastly


-Correspondence to NN
-How we honestly manage complexity in Extol
Questions..
 thanks

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