t stat for 2 populations (formulas)

Do we need to memorize these formulas?

I’ve skipped this part!

Every question I’ve seen on the test statistics in on the general understanding of the shape of the t-curve versus the normal, general questions where they ask about probability within 1, 2, or 3 stds of the mean… all things which can be done without calculations.

What formula?? Why would number of populations make a difference on a certain populations t-score? are you referring to F-statistic? All I memorized with CI & z, t statistics calculations…

mcf Wrote: ------------------------------------------------------- > Every question I’ve seen on the test statistics in > on the general understanding of the shape of the > t-curve versus the normal, general questions where > they ask about probability within 1, 2, or 3 stds > of the mean… all things which can be done without > calculations. So if it safe to ignore chi square, F etc? S

Remember Chebyshevs Inquality, 1 - (1/k^2) = percentage of data within k standard deviations.

I’ve NEVER seen a question on them… but I would definitely make sure to know that they are variance tests… when they are used… and maybe for f, that the greater stddev value goes in the numerator.

was it last year curriculum or is it new this year? S

this was definitely on last year’s. i skipped it.