STAtistics / Mr. Hansen	Name: _______________________________________
4/19/2012	Mr. Hansen’s use only (bonus point for spare batteries): _______

Test on Almost Everything (100 pts.)

• Calculator is OK throughout.
• If a gap is provided, provide adequate justification/explanation, and circle your answer.

1.	List the 7 steps in the standard procedure we use for hypothesis testing (letters + short summary of what should be done).
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2.	Define each of the following terms, and then use each term in a sentence.
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	P-value [as a conditional probability!]
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	Definition: ___________________________________________________________________
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	Used in a sentence: _____________________________________________________________
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	ES (effect size)
	Definition: ___________________________________________________________________
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	Used in a sentence: _____________________________________________________________
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	bias
	Definition: ___________________________________________________________________
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	Used in a sentence: _____________________________________________________________
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	Type II error
	Definition: ___________________________________________________________________
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	Used in a sentence: _____________________________________________________________
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3.	Suppose that 123 asthma sufferers are randomly divided into a placebo group (59 subjects) and an experimental group (64 subjects) in order to see whether a new medication (Itchalon) is safe and effective. In the placebo group, 15 of the subjects develop an embarrassing rash, and in the experimental group, 21 subjects develop a similar sort of rash. We wish to know whether this rash can be said to be a side effect of Itchalon, or whether the difference in occurrence is plausibly explainable by chance.
(a)	What is the statistic of interest in the sampling distribution? Give your answer using symbols, not numbers. (Hint: This statistic is actually a difference of 2 statistics.)
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(b)	Compute the standard error of the statistic cited in (a), assuming that we are performing a statistical test of the null hypothesis that the rash prevalence is the same regardless of whether Itchalon or a placebo is used. Show all work.
(c)	Compute the standard error of the statistic cited in (a), assuming that we are trying to find a confidence interval for the size of that statistic. If the answer is the same as (b), simply say that.
(d)	Check all assumptions for the situation described in #3, and state the test that you would use.
4.	An SRS of married couples in Fresno reveals the following data:
		man’s age	woman’s age
		45	38
		29	28
		71	58
		60	62
		39	36
		21	24
		44	39
		68	64
(a)	Is there evidence of a positive linear correlation between spouses’ ages? Perform all steps (except that you may omit the sketch of the sampling distribution if you wish.) Continue on the blank sheet provided, since there is not enough room below for the entire writeup.

(b)	Compute the standard error of the LSRL slope. Use correct notation for your answer. Work is optional.
(c)	Compute a 95% confidence interval for the LSRL slope. Show work.
(d)	State the value of the LSRL slope and interpret it in the context of this problem.
(e)	Estimate the age of a Fresno wife if the husband is 55 years old. Show work and correct notation.