Statistics question that will probably make me look stupid for asking it

If I have a population with 30 members and draw a 30 member sample from that population, the sample standard error of the mean should be zero because my population and sample size are the same, but of course the calculated standard error won’t be zero. What am I missing here?

Good question. Check out this link for the explanation. http://courses.wcupa.edu/rbove/Berenson/10th%20ed%20CD-ROM%20topics/section7_3.pdf

gamblingeconomist Wrote: ------------------------------------------------------- > Good question. Check out this link for the > explanation. > > http://courses.wcupa.edu/rbove/Berenson/10th%20ed% > 20CD-ROM%20topics/section7_3.pdf Thanks for the link. So basically if N and n are the same size the correction factor will be 0 and therefore standard error will be 0. Is that a correct statement?

correct

what are you people using the devil’s math (i.e. statistics) for in such a critical way that the standard error becomes important?

KJH Wrote: ------------------------------------------------------- > what are you people using the devil’s math (i.e. > statistics) for in such a critical way that the > standard error becomes important? What do you mean? Standard error is all important when trying to draw conclusions and test hypothesis from a data set.