stdevp( ) appears to be mislabeled

[parisse]

By the way, it should not be that essential. I mean sqrt(n/n-1) is 1.017... for n=30, in other words your confidence interval will be almost the same for a reasonable sample size (interval length will increase by less than 2%). If you make a poll of size n=1000 we are talking of less than 0.05% change. Insisting too much on the unbiaised vs biaised stddev estimate difference might miss more important comprehension.