AP Statistics / Mr. Hansen	Name: _______________________________________
3/6/2007

Test on Chapter 9 and Beginning of Chapter 10

• Calculator is OK throughout.
• If a blank is provided, give the short answer that fits best. If several lines of blanks are provided, write an essay of the approximate length indicated. Shorter is acceptable if you cover everything that needs to be said.
• If a gap is provided, provide adequate justification/explanation, and circle your answer.
• Point values are shown in parentheses in the left margin.

1. (20)	The two types of ___________ ___________ that we care the most about in our class are the sampling distribution of the ___________ ___________ (abbreviated ___________ ) and the sampling distribution of the ___________ ___________ (abbreviated ___________ ). The reason that it is so important to know the standard deviation of the statistics in these sampling distributions is ______________________________________________________________________ ______________________________________________________________________ ______________________________________________________________________ .
2. (12)	For tests or confidence intervals involving means, we may use either the ___________ or the ___________ procedures (give a letter for each). Of these two, the ___________ procedures (developed by an employee of the Guinness brewery who used the pseudonym ___________ ) are preferred. For tests or confidence intervals involving proportions, we use ___________ procedures, provided our rules of thumb are satisfied, even though the true sampling distribution is ___________ .
3. (8)	Write the definition of P-value. ______________________________________________________________________ ______________________________________________________________________ ______________________________________________________________________
4. (9)	A P-value of _____ (fill in a number) or _________ (fill in “less” or “greater”) is often considered to be the threshold of significance. Is there anything special about this value, or is it simply a common convention with no special importance? _______________________________________
5. (6)	A significance test addresses only the issue of whether a result is plausible or implausible given ______ alone. A significance test has nothing to do with whether a result is of any _____________ significance.
6. (15)	I have a die that I think may be unfair with regard to the probability of rolling a 6. In 100 rolls I obtain 14 sixes. Is there evidence that the die is unfair? Perform a significance test (all 7 steps). You do not need to show your work in the calculation of the test statistic and P-value.
7. (15)	In #6, compute a 90% confidence interval for the true probability of rolling a 6. Show your work. Give answer in both common formats (interval and “estimate ± m.o.e.”).

8. (15)

The commonly quoted distribution for American men’s heights is N(69, 3) in inches. I feel that the mean is actually higher than 69 inches, and I find an SRS of 29 American men who agree to be measured. Their mean height is 70.2 inches, with a standard deviation of 4.1 inches. Is there evidence that the mean of American men’s heights exceeds 69 inches? Perform all 7 steps of the statistical significance testing process. You do not need to show your work for the calculation of the test statistic and P-value.