The integrand is highly peaked. It is approximately an impulse function where much of the mass is concentrated at a very small interval. Plot the function and see for yourself. This is the likely cause of the problem.
Other types of integrands where you could experience problems are: integrands with singularity at either limit and slowly decaying oscillatory integrands. As to why integrate performs better than adaptIntegrate in this situation, I don't know. You have to study the two implementations. Wynn's epsilon algorithm is an extrapolation method for improving the convergence of a sequence. This could be an explanation for the better performance, but I cannot say for sure. Hope this is helpful, Ravi ------------------------------------------------------- Ravi Varadhan, Ph.D. Assistant Professor, Division of Geriatric Medicine and Gerontology School of Medicine Johns Hopkins University Ph. (410) 502-2619 email: rvarad...@jhmi.edu<mailto:rvarad...@jhmi.edu> [[alternative HTML version deleted]] ______________________________________________ R-help@r-project.org mailing list https://stat.ethz.ch/mailman/listinfo/r-help PLEASE do read the posting guide http://www.R-project.org/posting-guide.html and provide commented, minimal, self-contained, reproducible code.
