Sorry for not being more explicit in my emails, the code I am using was not generated by me therefore I was not in the position to share it.
Sorry if the information i have provided is insufficient or if I have wasted peoples time. Basically I have the information listed below I.e n and the quantiles of the random distribution and was wondering if a mean could be calculated from this or if I needed to modify the code to output the mean? the next columns are quantiles of the randomised PD distribution for significance testing # the probabilities are given as column names and are designed to allow 1- and 2-tailed # testing at the 0.05,0.01 and 0.001 levels, plus a spread at 0.1 intervals across the range. Sent from my iPhone On 29 Jan 2011, at 21:48, David Winsemius <dwinsem...@comcast.net> wrote: > > On Jan 29, 2011, at 9:39 AM, Peter Francis wrote: > >> Dear all, >> >> The data is generated from 1000 random samples of a phylogenetic tree to >> calculate phylogenetic diversity. I sampled the tree 1000 times at with >> various species communities (600) to get a random PD per community. I then >> want to test my observed PD with that of a random sample to test for >> significance. > > Color me puzzled. I thought you already had a test (the p value) and you > wanted an estimate for a mean given that you had a 95% CI. > >> However the script i used, output >> >> q0.005 q0.01 etc upto q0.995 > > Those look like names or labels for quantiles. This would move along a lot > faster if you gave a more complete listing of the output and the code used to > generate it. > > -- > David. >> >> But i wanted to know the mean PD value per community based on the output, >> and that is where i am struggling >> >> Thanks, >> >> Peter >> On 29 Jan 2011, at 02:16, Joshua Wiley wrote: >> >> Hi Peter, >> >> Do you know the formula used to calculate the confidence interval? I >> suspect it is possible with minimal algebraic manipulation of the CI >> formula to find what the mean is. Assuming a normal distribution (as >> David), then it is certainly possible to find. This wikipedia page >> might help: >> >> http://en.wikipedia.org/wiki/Confidence_interval >> >> And no, this is not really the correct place to ask. My basic rule of >> thumb is, "Does my question have anything to do with R? If my answer >> is, "No." then I usually look for somewhere else to post. Of course, >> for a comprehensive list, see the posting guide. >> >> If you are wondering if there is a function to do it for you, I am not >> sure, but it would be trivial to programme and if you show us the >> formula for it (the mean from the CI), we can certainly give you >> pointers for how to write your own :) >> >> Cheers, >> >> Josh >> >> On Fri, Jan 28, 2011 at 2:15 PM, Peter Francis <peterfran...@me.com> wrote: >>> Dear List, >>> >>> I am not sure if A) this is possible or B) the correct place to ask. >>> >>> I am looking to find the mean - i have n, and the two-tailed confidence >>> intervals 0.95 & 0.25 with a p-value of 0.05. >>> >>> Can i find the mean from this data ? >>> >>> Thanks >>> >>> Peter > > David Winsemius, MD > West Hartford, CT > [[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.
