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pelikan commented on Computational complexity and simulation of rare events of Ising spin glasses Thanks for the good comment. This presentation focused on hBOA and its performance analysis since it was an EC conference. hBOA actually outperforms even state of the art methods based on small random perturbations used typically in statistical physics on this problem like flat histogram Markov chain Monte Carlo, the complexity of which grows exponentially. Spin glasses are tough for all algorithms that make small randomized changes in solutions and are not capable of changing blocks of spins; this is because of their properties---there are energy barriers, many good local optima are relatively far from local optima, etc. This was investigated before in e.g. Dayal et al. (2004) who showed that flat histogram MCMC takes exponential time. Also, SA won’t do better than flat histogram MCMC. There is more on this in the paper associated with this presenttion: http://arxiv.org/abs/cs.NE/0402030 There is also an extended version of the paper which I can provide if this is not sufficient. Of course there is more to say to this, and for example cluster exact approximation works very well on spin glasses, and can in fact be combined with hBOA (http://medal.cs.umsl.edu/files/2006002. pdf). But that’s a very different method than the usual SA techniques (it’s based on maximum flow), it changes large domains of spins optimally in each step. If you want more pointers, I can provide :-) 3 years ago