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Chapter 4: Q 98. (page 260)

Two essential features of all statistically designed experiments are

(a) comparing several treatments; use the double-blind method.

(b) compare several treatments; use the chance to assign subjects to treatments.

(c) always have a placebo group; use the double-blind method.

(d) use a block design; use the chance to assign subjects to treatments.

(e) use enough subjects; always have a control group.

Short Answer

Expert verified

The correct option is (e) use enough subjects; always have a control group.

Step by step solution

01

Given information

All statistically planned experiments must have two characteristics.

02

Concept

A control group serves as a baseline against which the effects of the other treatments may be compared.

03

Explanation

In the question, we must determine what are the two most important characteristics of all statistically designed trials. Control, random assignment, and replication of a large number of individuals are the essential concepts of experimental design. Option (e), which is to utilize enough subjects and always have a control group, is the correct option.

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