An ANOVA F test is an extension of a

Question 1 options:

	two-sample z test.
	two-sample t test.
	two-sample test of proportions.
	a factorial ANOVA.

Question 2 (2 points)

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A manufacturer of infant formula is running an experiment usingthe standard (control) formulation and two new formulations, A andB. The goal is to boost the immune system in young children. Thereare 120 children in the study, and they are randomly assigned, 40to each of the three feeding groups. The study is run for twelveweeks. The variable measured is Total IGA in mg per dl. It ismeasured at the end of the study, with higher values being moredesirable. We are going to run a one-way ANOVA on these data. Thehypotheses tested by the one-way ANOVA F test are

Question 2 options:

	Ho: The mean IGA score is the same for all three formulas. Ha: The mean IGA score is higher for both treatment groups thanthe control.
	Ho: The mean IGA score is the same for all three formula. Ha: The mean IGA score is not the same for at least one of thethree formulas.
	Ho: The mean IGA score is the same for all three formulas. Ha: the mean IGA score is higher for at least one of the twotreatment groups than the control.
	Ho: The mean IGA score is the same for all three formulas. Ha: the mean IGA score is lower for at least one of the twotreatment groups than the control.

Question 3 (2 points)

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At what age do babies learn to crawl? Does it take longer tolearn in the winter when babies are often bundled in clothes thatrestrict their movement? Data were collected from parents whobrought their babies into the University of Denver Infant StudyCenter to participate in one of a number of experiments between1988 and 1991. Parents reported the age (in weeks) at which theirchild was first able to creep or crawl a distance of four feetwithin one minute. The resulting data were grouped by month ofbirth. The data are for January, May, and September.

Birth Month	Average Crawling Age	SD	n
January	29.84	7.08	32
May	28.58	8.07	27
September	33.83	6.93	38

Crawling age is given in weeks. Assume that data are threeindependent SRSs, one from each of the three populations (babiesborn in a particular month), and that the populations of crawlingages have Normal distributions. The overall mean response is:

Question 3 options:

	7.30
	31.05
	30.75
	3.70

Question 4 (2 points)

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I have three groups for which I want to perform an ANOVA. Theyhave standard deviations s1 = 2.5, s2 = 3.4, s3 = 6.4 and the plotsof the data indicate all samples are approximately Normal with nooutliers. Is the ANOVA appropriate?

Question 4 options:

	There is not enough information to tell.
	Yes
	There is too much information.
	No

Question 5 (2 points)

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A researcher is studying treatments for agoraphobia with panicdisorder. The treatments are to be the drug Imipramine at the twodoses 1.5 mg per kg of body weight and 2.5 mg per kg of bodyweight. There will also be a control group given a placebo. Thirtypatients were randomly divided into three groups of ten each. Onegroup was assigned to the control, and the other two groups wereassigned to the two drug treatments. After twenty-four weeks ontreatment, each of the subject's symptoms were evaluated through abattery of psychological tests, where high scores indicate alessening of symptoms. Assume the data for the three groups areindependent and approximately Normal with the same variance. AnANOVA F test tested the null hypothesis that there were nodifferences among the means for the three treatments that had aP-value less than 0.001. Which conclusion is correct?

Question 5 options:

	No choice is correct.
	There is strong evidence that the population mean scores for thehigher dose group of 2.5 must be larger than the population meanfor the lower dose group of 1.5.
	There is little evidence that the three population mean scoresmust all be different from each other because the P-valueis so small.
	There is strong evidence that the three population mean scoresmust all be different from each other because the P-valueis so small.