Mrs. Woods and Mrs. Bryan are avid vegetable gardeners. They use different fertilizers, and each claims that hers is the best fertilizer to use when growing tomatoes. Both agree to do a study using the weight of their tomatoes as the response variable. They had each planted the same varieties of tomatoes on the same day and fertilized the plants on the same schedule throughout the growing season. At harvest time, they each randomly select 15tomatoes from their respective gardens and weigh them. After performing a two-sample t test on the difference in mean weights of tomatoes, they get t 5.24and P 0.0008. Can the gardener with the larger mean claim that her fertilizer caused her tomatoes to be heavier?

(a) No, because the soil conditions in the two gardens is a potential confounding variable.

(b) No, because there was no replication.

(c) Yes, because a different fertilizer was used on each garden.

(d) Yes, because random samples were taken from each garden.

(e) Yes, because the P-value is so low

Short Answer

Expert verified

(a) No, because the soil conditions in the two gardens is a potential confounding variable.

Step by step solution

01

Step 1:Given information 

Given in the question that,

The test statistic : 5.24

The pvalue : 0.0008

02

Explanation 

If the effect of the factors on a dependent variable cannot be distinguished, they are said to be confused.

The tomatoes in the example could possibly be heavier due to the soil condition, which was overlooked in this case. Because soil condition was not measured, it may be considered a confounding variable.

As a result, the best solution is (a).

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