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Chapter 4: Q. R4.7 (page 288)

A recent study of 1000students at the University of Michigan investigated how to prevent catching the common cold. The students were randomly assigned to three different cold prevention methods for 6weeks. Some wore masks, some wore masks and used hand sanitizer, and others took no precautions. The two groups who used masks reported 10-50%fewer cold symptoms than those who did not wear a mask.

a. Does this study allow for inference about a population? Explain your answer.

b. Does this study allow for inference about cause and effect? Explain your answer.

Short Answer

Expert verified

a. This study does not allow for inference about a population because the students were not randomly selected from a larger population.

b. Yes.

Step by step solution

01

Part a. Step 1. Explanation

This study does not allow for inference about a population because the students were not randomly selected from a larger population.

02

Part b. Step 1. Explanation

This study allow for inference about cause and effect since treatments are assigned to the students, the study was an experiment and experiments allow for inference about cause and effect when the subjects were randomly assigned to the treatment groups and when there was a control group.

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Most popular questions from this chapter

Boosting preemies Do blood-building drugs help brain development in babies born prematurely? Researchers randomly assigned 53babies, born more than a month premature and weighing less than 3pounds, to one of three groups. Babies either received injections of erythropoietin (EPO) three times a week, darbepoetin once a week for several weeks, or no treatment. Results? Babies who got the medicines scored much better by age 4on measures of intelligence, language, and memory than the babies who received no treatment.

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