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Chapter 4: Q 93. (page 260)

The Community Intervention Trial for Smoking Cessation asked whether a community-wide advertising campaign would reduce smoking. The researchers located 11pairs of communities, each pair similar in location, size, economic status, and so on. One community in each pair participated in the advertising campaign and the other did not. This is

(a) an observational study.

(b) a matched pairs experiment.

(c) a completely randomized experiment.

(d) a randomized block design, but not matched pairs.

(e) a stratified random sample.

Short Answer

Expert verified

The correct option is (b) a matched pairs experiment.

Step by step solution

01

Given information

The researchers found 11 villages that were similar in terms of geography, size, economic position, and other factors.

02

Concept

The random assignment method assigns subjects to treatments based on chance. Before the treatments are applied, random assignment establishes treatment groups that are comparable (except for chance variance). In experiments, randomization and comparison combined prevent bias, or systematic favoritism.

03

Explanation

The community wanted to know if a community-wide advertising effort would help to reduce smoking. As a result, the population is made up of communities that have been divided into pairs based on how similar they are to limit variability among pairs. As a result, this experiment is a matched pairs experiment. As a result, option (b) is the proper choice.

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Most popular questions from this chapter

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