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Old 04-16-2012, 01:08 AM
antinucleon antinucleon is offline
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Join Date: Apr 2012
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Default Re: what is bias means?

Quote:
Originally Posted by yaser View Post
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.

Thanks dear prof first!
Assume we start at init hypothesis w=(0, 0, 0), init target function is w_t=(0.5, 2, 5)
As w = w + yx, y equals 0 or 1,x_n = (1, 0.5, 3) etc
When in iteration, w_0 = w_0 + y*x_0, as y and x_0 can only be 0 or 1, so the hypothesis function's threshold may be quite different from the target function, right?
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