I am new to BP, I am started learning it recently, unable to get the use of Bias node in BP...
Please explain it simply...
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Posted 11 March 2013 - 10:43 AM
By BP, what do you mean please?
Are you talking about back-propagation ? Yes you are, I didn't see your tag
If so, the bias is not related to back-propagation, but to Mc Culloch & Pitts model.
Any network model that use Mc Culloch & Pitts model must use a bias, as it is described in any good explanation.
The bias permit to shift the activation (or transfert) function, along x axis.
The common way to implement it is to add a constant input (1 or -1 usually) in input vector of each node and make its weight (i.e the bias) evolve like any other weight.
An analogy in 2D : the bias is like c in the line equation a.x+b.y+c=0
Edited by Tournicoti, 11 March 2013 - 03:04 PM.