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a)
To identify whether the observational study or experimental study.
a)
Answer to Problem 1.21E
This is an experimental study.
Explanation of Solution
Given:
Is there a relationship between physical fitness and leadership ability? To answer this question, researchers recruit 100 students who are willing to take part in an exercise program. The volunteers are divided into a low-fitness group and a high-fitness group on the basis of a physical examination. All students then take a test designed to measure leadership, and the results for the two groups are compared.
First need to understand about the experimental study and observational study:
Experimental study: Assigning people or things to groups and applying some treatment to one group, while the other group does not receive the treatment.
Observation study: In an observational study, measure or survey members of a sample without trying to affect them.
This study is an experimental study. The volunteers are divided into two groups and given a different treatment to other group.
b)
To find the population and variables.
b)
Answer to Problem 1.21E
The population is all people in the world and variables are High/low fitness group and leadership.
Explanation of Solution
Given:
Is there a relationship between physical fitness and leadership ability? To answer this question, researchers recruit 100 students who are willing to take part in an exercise program. The volunteers are divided into a low-fitness group and a high-fitness group on the basis of a physical examination. All students then take a test designed to measure leadership, and the results for the two groups are compared.
First need to understand about sample and population.
Population: It is the set of all the possible individuals possessing the characteristic of interest in a study.
Sample: it is the subset of population on which, the actual study performed and from which, the necessary measurements are taken.
The population is all people in the world. The variables are High/low fitness group and leadership.
c)
To explain why we prefer sample survey
c)
Explanation of Solution
Given:
Is there a relationship between physical fitness and leadership ability? To answer this question, researchers recruit 100 students who are willing to take part in an exercise program. The volunteers are divided into a low-fitness group and a high-fitness group on the basis of a physical examination. All students then take a test designed to measure leadership, and the results for the two groups are compared.
Because the students who volunteer for a fitness program are more interested in sports rather than general population. Hence, sample survey would help to choose such a sample.
Chapter 1 Solutions
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