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|    Message 964 of 1,954    |
|    Ted Dunning to All    |
|    Re: optimization    |
|    15 Mar 06 09:18:31    |
      From: ted.dunning@gmail.com              > Imagine a general heuristic problem.              It sounds to me like your definition of heuristic is different from the       standard definition.              > In general, as one increases the number of variables that need to be       optimized, the       > number of local optima in this optimization surface increases.              This definitely *can* happen, but it definitely does not happen in       general. Consider the quadratic bowl, \sum x_i^2. The number of local       minima is one (i.e. the global minimum) for any dimensionality number       of x_i's.              I think perhaps you are confusing the issue of multiple local minima       with the so-called curse of dimensionality which has more to do with       over-fitting than with the number of local minima. Over-fitting is due       to trying to fit noisy data with a model that has too many free       parameters. The critical value of "too many" is the key problem and       that has to do with things like generalization and empirical risk, not       local minima.              Can you say more about what you are really asking about?              [ comp.ai is moderated. To submit, just post and be patient, or if ]       [ that fails mail your article to |
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