Suppose you have 10 green bell peppers of various sizes that have been part of an experimental study. The study involved treating the peppers with a nutrient supplement that would produce larger and heavier peppers. To test the supplement, only 5 out of 10 peppers were treated with the supplement. All 10 peppers were of the same variety and grown under similar conditions, other than the treatment applied to 5 of the peppers.
First Randomization
Group A Group B
13.6 9.2
12.1 8.2
15.9 11.5
11.2 13.8
9.7 14.6
Second Randomization
Group A Group B
8.2 12.1
13.8 14.6
15.9 13.6
9.2 11.2
9.7 11.5
Third Randomization
Group A Group B
8.2 12.1
9.7 13.8
11.5 13.6
14.6 11.2
15.9 9.2
For each table, calculate the mean weight for each group, X^-A and X^-B and find the difference of the mean of group A and the mean of group B, (x^-A-x^-B)
PART A
After the first randomization, X^-A is ___,X^-B is___, and (X^-A-X^-B) is___
After the second randomization, X^-A is ___,X^-B is___, and (X^-A-X^-B) is___
After the third randomization, X^-A is ___,X^-B is___, and (X^-A-X^-B) is___
PART B
What does the difference of the means of each group indicate? What makes the mean of one group greater or less than the mean of the other group?
PART C
What does a mean difference of zero between the two groups indicate?