# One-tailed Hypopheses testing. F-statistic.

Hello. I have some misunderstanding. For example we have to populations with associated S1 n1 and S2 n2 standard deviation and sample size correspondingly. If i want to test wether S1^2 is greater S2^2 how shold I define null and alternative hypotheses and calculate appropriate F-statistic. Please explain the logic. Thanks.

Always put the bigger one on top and halve your alpha…

Does it mean that the form of Hypopheses condition does not matter? I just put the bigger variance in the numirator, then find upper critical value of F statistic using numerator degree of freedom in horisontal and denumerator degree of freedom in vertical values of F distribution table?

Right. Remember that by putting the bigger one on top, you need to halve alpha to look up critical value.

" you need to halve alpha to look up critical value" alpha - level of significance?

Yep

Am i right that it is stated in condition of the test? e.g. “with the 5% level of significance…”

do you think/know if L1 candidates are expected to know the hypothesis testing formulas (computing the test statistic etc)? should I expect -for this particular part of quant - some “qualitative” questions (interpretation) or proper calculations? thanks