ch1 quiz Essay

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Chapter 1 quiz Total Grade: 10 (of possible 15 points)
Question 1 of 11 Score: 1 (of possible 1 point)
In 1982, 490,000 subjects were asked about their drinking habits. Researchers tracked subjects' death rates until 1991, and found that adults who regularly had one alcoholic drink daily had a lower death rate than those who did not drink. Most of the subjects were middle-class, married, and college-educated.
A news headline, reporting the medical study as "Daily Drink Cuts Death!" is:

Misleading; it implies that there is a causal connection between improved health and the habit of having one drink daily; however, causation cannot be deduced from an observational study.

Misleading; we can never infer causation from randomized experiments.

Accurate; stratified random samples lead to randomized experiments, from which we cannot infer causation.

Accurate; there is fundamentally solid anecdotal evidence that one drink daily increases life length and cuts death.
Answer Key: A
Question 2 of 11 Score: 1 (of possible 1 point)
A town obtains current employement data by polling 10,000 of its citizens this month. This observational data is

A. prospective B. retrospective C. cross-sectional D. none of the above
Answer Key: C
Question 3 of 11 Score: 0 (of possible 1 point)
In a statistical study, the population is:

The people or objects studied in the sample survey.

All people in the United States.

The group of people from whom data cannot be collected.

The group of people or objects for which conclusions are to be made.
Answer Key: D
Question 4 of 11 Score: 1 (of possible 1 point)
The design of a study is biased if it systematically favors certain outcomes.

Answer Key: True
Question 5 of 11 Score: 1 (of possible 1 point)
To reduce sampling bias, we need to

A. increase the sample size.

B. decrease the population size.

C. randomize appropriately.

D. avoid the use of randomization.
Answer Key: C
Question 6 of 11 Score: 1 (of possible 1 point)
At a party there are 30 students over age 21 and 20 students under age 21. You choose at random 3 of those over 21 and separately choose at random 2 of those under 21 to interview about attitudes about alcohol. This is an example of a

A. stratifed random sample.

B. block sample.

C. simple random sample.

D. voluntary response sample.
Answer Key: A
Question 7 of 11 Score: 1 (of possible 1 point)
Twenty students agreed to participate in a study on colds. Ten were randomly assigned to receive vitamin C, and the remaining 10 received a tablet that looked and tasted like vitamin C but in fact contained only sugar and °avoring. Neither the students nor the researchers who actually carried out the study and analyzed the data knew which treatment group the students were in. The students were followed for 2 months to see who came down with a cold and who did not. Below are some terms. Which one does not apply to this study?

A. matching B. double-blind C. randomized experiment

D. double-blind Answer Key: A
Question 8 of 11 Score: 0 (of possible 1 point)
One hundred students are selected at random from each of the freshman, sophomore, junior, and senior classes at a college. This is a(n)

A. simple random sample

B. cluster sample

C. stratified sample

D. multistage sample
Answer Key: C
Question 9 of 11 Score: 1 (of possible 1 point)