Around the internet, I have seen scattered references to the idea of rescaling an objective function and using that as a PDF for the purpose of optimization. (On this site for example: Do optimization techniques map to sampling techniques?) Can someone point me to a place where I can learn more about this method? (Papers, blog posts, lectures, etc.)
The idea, as I've seen it, is to take your objective function $f(x)$ and create a new function $g(x) = e^{kf(x)}$, where $k$ is a very large number for a maximization problem or a very large negative number for a minimization problem. The new function $g(x)$ will then be much higher at the global optimum than anywhere else. If $g(x)$ is then treated as an unnormalized probability density function, most samples drawn from that distribution will be around that optimum.
Things I want to know include, but are not limited to:
- Which sampling algorithms are effective for these probability functions?
- Why is this method not used more frequently? (It seems like it could be be so effective). In other words, are there arguments against it?
- Are there any variants of this method that improve efficiency efficiency or performance?