Statistics questions

Statistics
Tutor: None Selected Time limit: 1 Day

Mar 10th, 2015

The P-value of the test statistic? :-/ It isn't really clear to me what the question is asking. It's especially bad that it asks you for a test statistic without telling you what the test is!

1) If there's a test, it's likely to be of the Mayor's belief that >30% of the residents favour annexation. If this is so, we'll get a very high p (>0.5). That's the only test that makes much sense given the wording.

2) But more normally, we would test against a null hypothesis with a fixed value, not an inequality. E.g. we would test the hypothesis that population mean = 30 (not >30 as in the question).


I'll test 1) since that is the only possible test I can read from the question. But be warned, it doesn't make much sense to me that that is what you'd be asked. It's very badly worded.


Anyway , for a proportion, standard deviation = sqrt(p(1-p))

So sample sd = sqrt(0.33*0.67)

= 0.470

So standard error around the mean = sd/sqrt(n)

= 0.470/sqrt(1000)

= 0.01487

So test statistic t with df=n-1 = 999:

1) For testing pop. mean >30 we have:

t = (0.3-0.33)/0.01487

= -2.018

So P(t, df=999) = 0.978


Mar 10th, 2015

Are you studying on the go? Check out our FREE app and post questions on the fly!
Download on the
App Store
...
Mar 10th, 2015
...
Mar 10th, 2015
Dec 7th, 2016
check_circle
Mark as Final Answer
check_circle
Unmark as Final Answer
check_circle
Final Answer

Secure Information

Content will be erased after question is completed.

check_circle
Final Answer