[r] Critical t values in R

Josh's comments are spot on. If you are not super familiar with critical values I'd suggest playing with qt, reading the manual (?qt) in conjunction with looking at a look up table (LINK). When I first moved from SPSS to R I created a function that made critical t value look up pretty easy (I'd never use this now as it takes too much time and with the p values that are generally provided in the output it's a moot point). Here's the code for that:

critical.t <- function(){
    cat("\n","\bEnter Alpha Level","\n")
    alpha<-scan(n=1,what = double(0),quiet=T)
    cat("\n","\b1 Tailed or 2 Tailed:\nEnter either 1 or 2","\n")
    tt <- scan(n=1,what = double(0),quiet=T)
    cat("\n","\bEnter Number of Observations","\n")
    n <- scan(n=1,what = double(0),quiet=T)
    cat("\n\nCritical Value =",qt(1-(alpha/tt), n-2), "\n")
}

critical.t()