
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 <dwinsemius@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 <peterfrancis@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
> 

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