Travis is testing the effects of a new fertilizer on the growth of a plant. He had 30 plants that were randomly split into two groups. Group 1 was given no fertilizer, and in Group 2 each plant was given a cup of fertilizer. Two weeks later, the height of each plant was measured. Travis found that the mean of the heights from Group 2 was 1.5 inches taller than the mean of the heights from Group 1.
To confirm that the fertilizer was the cause of the difference, Travis re-randomized the data into two groups 300 times and looked at the resulting differences in the means. The difference in the means was greater than or equal to 1.5 inches 2 times out of the 300 trials.
What do the results of the re-randomization mean in confirming Travis' test on the effect of the fertilizer? (I chose B, but I'm not sure)
A. They allow Travis to conclude confidently that the fertilizer caused the difference in the mean heights of the plants.
B. They allow Travis to conclude confidently that the fertilizer did not cause the difference in the mean heights of the plants.
C. There is no information gained from the re-randomization on the effect of the fertilizer.
1 answer