Hypothesis Tests Comparing Standard Deviations of Two Samples
The F-Distribution Table
Yet another distribution! F-values are pretty similar to chi-square, except they're so crazy that you actually need two different degrees of freedom, and therefore the table takes up like 10 pages at the back of your textbook. Kinda nuts, so expect to be doing these mostly on your calculator.
Comparing Standard Deviations of Two Samples
This type of problem isn't covered by many stats classes, because let's face it, standard deviation isn't something people go around hypothesizing about unless they have a lot of time on their hands (or they're running a high-precision factory). Nonetheless, we do have to cover it, so I cooked up a couple of silly examples to get us there.
If you do not have an account, you should get one, because it is awesome! You can save a playlist for each test or each chapter, and save your "greatest hits" into a "watch right before the final" list (not that we recommend cramming, but when in Rome...)