Koen (dazero) (1/28/2011)
Then why is the explanation confusing? I find it pretty clear...The explanation is "The denominator of the variance for a sample population is n  1, resulting in division by zero." This suggests it should give an error, and doesn't explain why it results in null instead. I guessed wrong, but I'm not sure what the question was supposed to prove, other than if you apply a function wrongly then you get a meaningless answer!
