Thanks for the help. I appreciate. On Mon, May 16, 2011 at 10:19 PM, Greg Snow <greg.s...@imail.org> wrote:
> So there is no maximum value, just a minimum (greater than 0)? Correct? In > that case the sample option will not work (unless you choose some really > high value and say that you wont go above that), but the rejection sampling > would still work. How efficiently it works will depend on how much > probability a regular poisson would put into the truncated region. > > > > Another possibility is to find the probability of being in the truncated > region, then generate a uniform between that value and 1, then feed that > uniform into the qpois function. > > > > *From:* cassie jones [mailto:cassiejone...@gmail.com] > *Sent:* Monday, May 16, 2011 7:46 PM > *To:* Greg Snow > *Cc:* r-help@r-project.org > *Subject:* Re: [R] simulation from truncated poisson > > > > It is truncated from left. > > On Mon, May 16, 2011 at 6:33 PM, Greg Snow <greg.s...@imail.org> wrote: > > Which direction is it truncated? (only values less than a allowed or only > greater?). > > One simple approach is rejection sampling, just generate from a regular > poisson distribution, then throw away any values in the truncated region. > Another approach if the legal values are those from 0 to a, so that there > is a finite number of possibilities, then you can use the sample function > with replace=TRUE and using probabilities from the poisson in the legal > range. > > > -----Original Message----- > From: r-help-boun...@r-project.org [mailto:r-help-boun...@r-project.org] > On Behalf Of cassie jones > Sent: Monday, May 16, 2011 5:28 PM > To: r-help@r-project.org > Subject: [R] simulation from truncated poisson > > Dear all, > > I need to simulate values from a Poisson distribution which is truncated at > certain value 'a'. Can anyone tell me if there is in-built package in R > which can simulate from a truncated Poisson? If not, what should be the > steps to write a function which would do that? > > Thanks in advance. > > > Cassie > > [[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. > > > [[alternative HTML version deleted]]
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