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Q.61

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The Practice of Statistics for AP

Found in: Page 731

Book edition 4th

Author(s) David Moore,Daren Starnes,Dan Yates

Pages 809 pages

ISBN 9781319113339

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Short Answer

Design (4.2) Was this an observational study or an experiment? Justify your answer.

The study is the experimental study.

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Step by Step Solution

TABLE OF CONTENTS :

TABLE OF CONTENTS

Step 1: Given Information

The data is given in the question that,

Step 2: Explanation

Observational study: An observational study is one where the participants are simply monitored based on certain criteria without changing them.

Experimental Study:

If some treatments are applied to the individuals in order to observe the effectiveness of the treatments then the study is termed an experimental study.

A study is conducted to determine whether the answers of the respondents are being affected if the rating scale is changed or not. For this a simple random sample of $90$ students is selected from the total population of $1000$ students. The first $45$ students are given a scale of $1$ to $5$ and the remaining $45$ students are given a scale of $0$ to $4$ .

In this study: the different scaling is given to two groups of students for observing the effect of scale on the responses to the question. This shows that: the study is an experiment.

Thus, the study is an experimental study.

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