I'm learning Monte-Carlo approach in sampling. There I faced with ways of how to draw samples from given distribution. But can you give me an example of a distribution which can not be trivially simulated as normal or binomial distribution?
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4$\begingroup$ It's still not quite clear what your last sentence is asking. Do you mean "cannot be as trivially simulated as normal or binomial"? What's your trivial means of simulating a binomial? What makes something trivial or non-trivial more generally? $\endgroup$– Glen_bCommented Jun 2, 2015 at 10:46
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$\begingroup$ von Mises-Fisher is also such an example, cf. this previous post on Cross Validated. $\endgroup$– micCommented Jun 18, 2015 at 12:39
2 Answers
Drawing gamma random numbers usually requires rejection sampling, it is less trivial.
I assume that you refer to trivial if the CDF is invertible, or conversion from the uniform to the target distribution can be resolved with thresholds.
In this earlier Cross Validated question, a density defined as $$h_β(r)∝(1−w_{\mu,τ}(r))f_{β_0}(r)+w_{\mu,τ}(r)g_{ϵ,σ}(r)$$ is proposed, with a non-trivial simulation solution.
In my class, I usually give the benchmark density target $$h(x)\propto \{1+\sin^2(2x)+\sin^4(4x)\}\exp\{-x(1+\cos^2(4x)+\cos^4(2x))\}$$ to simulate. You can make similar examples by piling up complex but upper bounded terms.