Hello,

I'm using var.test to do a simple F-test for equality of variances. I think
I'm missing something small here:

> m<-rnorm(10,sd=1)
> n<-rnorm(5,sd=1)
> var.test(m,n)

    F test to compare two variances

data:  m and n
F = 13.7438, num df = 9, denom df = 4, p-value = 0.02256
alternative hypothesis: true ratio of variances is not equal to 1
95 percent confidence interval:
  1.543430 64.844094
sample estimates:
ratio of variances
          13.74375

> qf(.0250,9,4)*var(m)/var(n)
[1] 2.912997 <- correct degrees of freedom (I think!) and does not match
var.test lower bound
> qf(.0250,4,9)*var(m)/var(n)
[1] 1.543430       <-matches var.test lower bound with degrees of freedom
reversed
>

It seems that the F-test in var.test is getting the degrees of freedom mixed
up. Outside calculators seem to agree with the qf function.

So, am I misunderstanding something?

Thank you!

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