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Chapter 4: Q. 90 (page 269)

Two essential features of all statistically designed experiments are

a. comparing several treatments; using the double-blind method.

b. comparing several treatments; using chance to assign subjects to treatments.

c. always having a placebo group; using the double-blind method.

d. using a block design; using chance to assign subjects to treatments.

e. using enough subjects; always having a control group.

Short Answer

Expert verified

The correct option is (e). using enough subjects; always having a control group.

Step by step solution

01

Given information

Two basic highlights of all statistically planned tests are

02

Explanation

Statistically planned tests have three fundamental highlights: replication, randomization, and control. Replication implies that we have to replicate the test with numerous subjects, and hence we have got to utilize sufficient subjects. Randomization implies that we get randomization by arbitrarily selecting our subjects or haphazardly doling out the subjects to treatment groups. Control means that we require a control group (which may be a fake treatment group, but a fake treatment group isn't continuously required, such as when managing with plants or animals). We at that point note that reply alternative (e) best fits the basic highlights because it alludes to replication and control.

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