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Chapter 4: Q 92. (page 260)

In the experiment of the previous exercise, the 240 subjects are labeled 001 to 240 The software randomly assigns 60 subjects to each of the four diets. This is

(a) a completely randomized design.

(b) a randomized block design.

(c) a matched pairs design.

(d) an observational study.

(e) an SRS.

Short Answer

Expert verified

The correct option is (a) a completely randomized design.

Step by step solution

01

Given information 

001 through 240 are the numbers assigned to the 240 subjects. The software assigns 60 people to each of the four diets at random.

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 240 individuals are labelled 001 to 240 in the previous exercise, and the soft reassigns sixty participants to each of the four diets. The subjects are then placed into treatment groups at random. As a result, no blocks or pairs are employed. Because therapies are used, this is not an observational research. As a result, unlike a random assignment, this is a simple random pick. As a result, option (a) is the proper choice.

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Most popular questions from this chapter

In the cornfield An agriculture researcher wants to compare the yield of five corn varieties: A, B, C, D, and E. The field in which the experiment will be carried out increases in fertility from north to south. The researcher therefore divides the field into twenty five plots of equal size, arranged in five east–west rows of five plots each, as shown in the diagram.

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(b) Should the researcher use the rows or the columns of the field as blocks? Justify your answer.

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