Quiz 2 Review

Much better this week! Keep it up. If you see (half) anywhere on your quiz that means that you missed an earlier question, which caused you to miss the later question. So you did everything correct on the later question, but you didn't get the right answer because of the earlier mistake.

For example suppose you mess up calculating the p-value, so now it's bigger than \(\alpha\) when it should have been smaller. That messes you up in step 3 since you fail to reject \(H_0\) when you should have rejected it. You get half credit for these. Ask me if you have any questions about grading.

A01

#1

The first step is to recognize the problem. As you're reading the prompt, you should be asking yourself:

Still some confusion about the parameters:

#2

For the p-value:

#3

Deciding: What is the p-value?

#4/5

Can we conclude that more underclassmen attend the game than upperclassmen? Not quite. What if \(N_2 >> N_1\), i.e. there are a lot more upperclassmen in the population?

B42

#1

The first step is to recognize the problem. As you're reading the prompt, you should be asking yourself:

Still some confusion about the parameters:

The alternative hypothesis is what we're testing: Are current users less likely than nonusers to prefer the new product. \(H_a: p_1 < p_2\)

#2

Which way to shade? We shade evidence for \(H_a\) so to the left of the \(Z\) in this case.

#3

Deciding: What is the p-value?