Dear List I have run into some problems with boot.ci from package boot. When I try to obtain a confidence interval of type bca, boot.ci() returns the following error when the data set i large: Error in bca.ci(boot.out, conf, index[1L], L = L, t = t.o, t0 = t0.o, : estimated adjustment 'a' is NA
Below is an example that produces the above mentioned error on my machine. library(boot) #The wrapper function: w.mean <- function(x, d) { E <- x[d,] return(weighted.mean(E$A, E$B))} #Some fake data: test <- data.frame(rnorm(1000, 5), rnorm(1000, 3)) test1 <- data.frame(rnorm(10000, 5), rnorm(10000, 3)) names(test) <- c("A", "B") names(test1) <- c("A", "B") # Getting the boot object and the CI, seem to works fine bootout <- boot(test, w.mean, R=1000, stype="i") (bootci <- boot.ci(bootout, conf = 0.95, type = "bca")) # Now with a bigger data set, boot.ci returns an error. bootout1 <- boot(test1, w.mean, R=1000, stype="i") (bootci1 <- boot.ci(bootout1, conf = 0.95, type = "bca")) Does anyone have an idea as to why this happens? (Session info below) Best, Lars > sessionInfo() R version 2.12.1 (2010-12-16) Platform: x86_64-apple-darwin9.8.0/x86_64 (64-bit) locale: [1] da_DK.UTF-8/da_DK.UTF-8/C/C/da_DK.UTF-8/da_DK.UTF-8 attached base packages: [1] stats graphics grDevices utils datasets methods base other attached packages: [1] boot_1.2-43 loaded via a namespace (and not attached): [1] tools_2.12.1 ______________________________________________ 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.