The midrange is a measure of variation.
Indicate whether the statement is true or false
Q. 2In order to make a decision using the minimax criterion, we select the action that gives the _______ of the
_______ opportunity losses.
Fill in the blank(s) with correct word
Q. 3If two events A and B are __________, then P(A and B) = P(
A) P(B).
A) independent B) mutually exclusive C) simple events D) complements
Q. 4In a hypothesis test, indicates
A) the area of the rejection region for the null hypothesis.
B) the probability of a Type II error.
C) whether the test is one-tailed or two-tailed.
D) the probability of accepting the null hypothesis.
Q. 5Sampling with replacement from a finite population is, in effect, sampling from an infinite population.
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Q. 6Grape juice and blood pressure Researchers who wanted to see if drinking grape juice could help people lower their blood pressure got 120 non-smokers to volunteer for a study.
They measured each person's blood pressure and then randomly divided the subjects into two groups. One group drank a glass of grape juice every day while the other did not. After sixty days the researchers measured everyone's blood pressure again. They reported that differences in changes in blood pressure between the groups were not statistically significant.
a. Was this an experiment or an observational study? Explain briefly.
b. Briefly explain what not statistically significant means in this context.
c. Briefly explain why the researchers randomly assigned the subjects to the groups.
d. Since everyone's blood pressure was measured at the beginning and at the end of the study, the researchers could have simply looked at the grape juice drinkers to see if their blood pressure changed. Briefly explain why the researchers bothered to include the control group.
e. Briefly explain why the researchers studied only non-smokers.
f. Other researchers now plan to replicate this study using both smokers and non-smokers. Briefly describe the design strategy you think they should use.
Q. 7If some of the frequencies are greater than 1, the number of rows in the frequency distribution is equal to the
size of the sample.
Indicate whether the statement is true or false
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