regression.with.ci <- function(regress.out, level=0.95)
{
################################################################
#                                                              #
#  This function takes the output from an lm                   #
#  (linear model) command in R and provides not                #
#  only the usual output from the summary command, but         #
#  adds confidence intervals for intercept and slope.          #
#                                                              #
################################################################
usual.output <- summary(regress.out)
t.quantile <- qt(1-(1-level)/2, df=regress.out$df)
intercept.ci <- summary(regress.out)$coefficients[1] + c(-1, 1) * t.quantile * summary(regress.out)$coefficients[3]
slope.ci <- summary(regress.out)$coefficients[2] + c(-1, 1) * t.quantile * summary(regress.out)$coefficients[4]
output <- list(regression.table = usual.output, intercept.ci = intercept.ci, slope.ci = slope.ci)
return(output)
}