[R] prop.test() references

[Marc Schwartz]

On Thu, 2007-02-01 at 07:22 +0100, Jean lobry wrote:
> Dear R-help,
> 
> I'm using prop.test() to compute a confidence interval for a proportion
> under R version 2.4.1, as in:
> 
> prop.test(x = 340, n = 400)$conf
> [1] 0.8103309 0.8827749
> 
> I have two questions:
> 
> 1) from the source code my understanding is that the confidence
> interval is computed according to Wilson, E.B. (1927) Probable
> inference, the law of succession, and statistical inference.
> J. Am. Stat. Assoc., 22:209-212.
> Is it correct?

Yes.

> 2) The doc says "Continuity correction is used only if it does not exceed
> the difference between sample and null proportions in absolute value."
> Does someone has a reference in which this point is discussed?

I believe that this is a modification by Newcombe. See:

Newcombe RG: Two-Sided Confidence Intervals for the Single Proportion:
Comparison of Seven Methods. Statistics in Medicine 1998;17:857-872.

Newcombe RG: Interval Estimation for the Difference Between Independent
Proportions: Comparison of Eleven Methods. Statistics in Medicine
1998;17:873-890.


HTH,

Marc Schwartz