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Chapter 4: Q AP1.4. (page 276)

For a certain experiment, the available experimental units are eight rats, of which four are female (F1,F2,F3,F4) and four are male (M1,M2,M3,M4) There are to be four treatment groups,A,B,C, and D If a randomized

block design is used, with the experimental units blocked by gender, which of the following assignments of treatments is impossible?

(a) A → (F1, M1), B → (F2, M2),

C→ (F3, M3), D → (F4, M4)

(b) A → (F1, M2), B → (F2, M3),

C→ (F3, M4), D → (F4, M1)

(c) A → (F1, M2), B → (F3, F2),

C→ (F4, M1), D → (M3, M4)

(d) A → (F4, M1), B → (F2, M3),

C→ (F3, M2), D → (F1, M4)

(e) A → (F4, M1), B → (F1, M4),

C→ (F3, M2), D → (F2, M3)

Short Answer

Expert verified

The correct option is

A→(F1,M2),B→(F3,F2),C→(F4,M1),D→(M3,M4)

Step by step solution

01

Given information

Number of females = F1, F2, F3, F4 = 4

Number of males = M1,M2,M3,M4 = 4

02

Concept

The treatments are randomly assigned to all of the experimental units in a completely randomized design.

03

Explanation

The gender-blocking design is utilized with units.

Number of treatments A,B,C,D=4

Gender is used to block experimental units.

Male and female combinations of any kind are possible, but they must not be of the same gender.

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