Basic Statistics - P-values and Proportions?

Question

What's the difference between the two when you are hypotheses testing?

Thanks!

Answer 1

when doing a hypothesis test with proportions you are testing something about a sample proportion. For instance say you randomly take 100 cookies from a group that is supposedly 50% chocolate chip. Since you took a sample of 100 and got only 10 chocolate chip you decide to test whether the proportion of chocolate chip cookies is actually 50%. So you have:

Ho = p = 50% = 0.5
Ha = p < 50% = < 0.5

The proportion of chocolate chip cookies in your sample is 10%.

Now after you work through the calculations you should get a standard normal (N~(0,1)) z statistic. The p-value associated with the test is the probability of a more extreme result than your observed result given the Ho is true...

In this context the p-value would be the probability Z is less than the calculated Z statistic given the overall proportion of chocolate chip cookies is 50%.

If you need/want more info or clarification message me and I'll try to clear anything up.