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Old 04-15-2012, 09:01 PM
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Default Re: what is bias means?

Quote:
Originally Posted by antinucleon View Post
I am confused with the bias.
In wikipedia, w0 is called threshold, so I think it may be any value.
But in this lecture, we make this tuple (1, x0, y0). When in perception process, all changes performed on w0 is +1 or -1, it can't reach the degree of 0.1 or more precious.
Where am I wrong?
This may be a case of notational confusion, as the lectures follow the book notation, not wikipedia. The tuple in the lecture was (x_0,x_1,x_2) which is the input vector {\bf x}, and x_0=1 by definition. The weight vector is (w_0,w_1,w_2) and all 3 coordinates can assume different values, with w_0 being the threshold (also referred to as bias) coordinate.
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