Surrogate Functions


In some optimizations problems, the objective-function is just too complicated to evaluate directly at every iteration, and in this case, we use surrogate functions, functions that mimic most of the properties of the true objective-function, but that is much simpler analytically and/or computationally.

Lately, I have done some thinking about what properties a surrogate function (or surrogate model) should have to be practical.

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How many eyeballs to make a bug shallow?


In the The Cathedral and the Bazaar, Eric Raymond said that “Given enough eyeballs, all bugs are shallow.” Of course, what he meant is when you have a large enough tester base and lots of developers, almost all bugs are found, characterized (i.e., how to make them reproducible and what are the effects) and fixed by someone in the developer group. This appears to me as somewhat optimistic and begs the question… how many eyeballs does it take to make a bug shallow?

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