search for: z_lci

Displaying 2 results from an estimated 2 matches for "z_lci".

2009 Aug 27
1
standard error associated with correlation coefficient
I want the standard error associated with a correlation. I can calculate using cor & var, but am wondering if there are libraries that already provide this function. [[alternative HTML version deleted]]
2009 Sep 01
1
Logistic Politomic Regression in R
...b31d0ace49300@mail.gmail..com> Content-Type: text/plain Here are some options for confidence intervals. #by hand sample_r <- .5 n_sample <- 100 df <- n_sample-1 fisher_z <- 0.5*(log(1+sample_r)-log(1-sample_r)) se_z <- 1/sqrt(n_sample-3) t_crit <- qt(.975,df ,lower.tail=TRUE) z_lci <- fisher_z - (t_crit * se_z) z_uci <- fisher_z + (t_crit * se_z) (r_lci <- tanh(z_lci)) (r_uci <- tanh(z_uci)) # Compare to the CIr function in psychometric library #that uses standard normal instead of t library(psychometric) CIr(sample_r,n_sample) And see http://www.stat.umn.edu...