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From: 93funkst@wave.scar.utoronto.ca (FUNK  STEVEN LESLIE,,Student Account)
Subject: Re: Simple NN problem for Beginners
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Organization: University of Toronto - Scarborough College
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Date: Sat, 10 Dec 1994 18:55:01 GMT
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In article 2ek@nova.umd.edu, collins@nova.umd.edu (Jim C) writes:
> Ok, here's a simple problem. The inputs to our NN are a string like:
> 0 1 1 0   for which the desired output is 0
> The desired output is "0" if the total number of "1"s in our 4-bit
> string is less than three . The desired output is "1" is the total 
> number of "1"s is three or four. 
> So how to we set up the net?
> Jim C.


Hi,

	This is a seriously easy problem.  All you want to do is connect the input units to the output unit in such a way that the output unit is on only active if at least three of the input units are on.  The simplest way is to give each connection a weight of one and set the threshold of the output unit to 2.9.  Or you could set each connection weight to 0.49 and leave the output units threshold at 1.  In each case the accumulated activation won't trigger the output unit until there are atleast 3 units contrib
uting.

Hope this helps.

Steve Funk
93funkst@wave.scar.utoronto.ca


