On Tue, 10 May 2005, Briggs, Meredith M wrote:

I'm not sure I'm using boot correctly:

You are not using argument `i'. Have you read the reference: `boot' is
support software for a book? (Or even the definition of `statistic' on the help page?) The bootstrap sample in your case is x[i], not x.


I have a list of values for a variable in BUCKET[, j] I want to use function 'boot' to estimate a confidence interval on the mean of the non-zero data. The data can be bi-polar or skewed. Is this the correct use of boot to establish a mean and standard deviation or median and percentiles?


x<-BUCKET[, j] mean.fun<-function(x,i) {mean(x[x>0])} median.fun<-function(x,i) {median(x[x>0])} print(mean.fun(x)) print(median.fun(x)) B.mean<-boot(x,mean.fun,R=999) B.median<-boot(x,mean.fun,R=999) print(B.mean) print(B.median)

I need the 'boot' function to sample repeatedly from the density distribution of the raw data and calculate means, medians etc.

How do I pull out the mean, median, deviations and percentiles into variables within R?


--
Brian D. Ripley,                  [EMAIL PROTECTED]
Professor of Applied Statistics,  http://www.stats.ox.ac.uk/~ripley/
University of Oxford,             Tel:  +44 1865 272861 (self)
1 South Parks Road,                     +44 1865 272866 (PA)
Oxford OX1 3TG, UK                Fax:  +44 1865 272595

______________________________________________
[email protected] mailing list
https://stat.ethz.ch/mailman/listinfo/r-help
PLEASE do read the posting guide! http://www.R-project.org/posting-guide.html

Reply via email to