# Calculating Cohen's kappa values

I'm trying to better understand Cohen's kappa coefficient to analyze some data. I understand the equation and how to use it (I think), but I have a simple question.

If you navigate to the wiki page on Cohen's kappa, you'll find an example where 50 people are applying for a grant and two people (call them admissions people) are saying either "yes, fund it" or "no, don't fund it". Consider the same example but with different values now. Suppose person A says "yes" to all grants, and person B also says "yes" to all grants. In this scenario, and following from the wiki article, the kappa value ends up being $0/0$, when in reality, it should be pretty high (and close to $1$) as both person A and B agreed on everything.

How did you get $0/0$? It looks to me like $\dfrac{1-\Pr(e)}{1-\Pr(e)}$. That's not $0/0$. – Michael Hardy Jan 25 '13 at 17:02
@MichaelHardy: What value would you assign to Pr(e)? – user59652 Jan 25 '13 at 17:40