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Chapter 4: Q 95. (page 260)

Corn variety 1 yielded 140 bushels per acre last year at a research farm. This year, corn variety 2,

planted in the same location, yielded only 110 bushels per acre. Unfortunately, we don’t know

whether the difference is due to the superiority of variety 1 or to the effect of this year’s drought. This is an example of

(a) bias. (d) the placebo effect.

(b) matched pairs design. (e) replication.

(c) confounding.

Short Answer

Expert verified

The correct option is (c) confounding.

Step by step solution

01

Given information

At a research farm, corn variety 1 produced 140 bushels per acre last year. Corn variety 2 yielded just 110 bushels per acre this year when planted in the same spot.

02

Concept

Confounding occurs when the effects of two variables on the same response variable cannot be distinguished from one another.

03

Explanation

We don't know if the difference is attributable to the excellence of variety one or the effect of this year's drought in this question. Confounding occurs when a variable whose effect on an experiment is not accounted for has an effect on the outcomes. The drought was not a controlled variable, so it confounds the results. As a result, this is a matched pairs design example. Option (c) is the best choice.

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