Practice Test

Question 16 • Statistics

Using the dotplot and the difference in mean ratings from the samples, is there convincing evidence that the one detergent is better than the other?

Answer

No, because a difference in mean rating of 1 point 5 or more occurred 23 out of 200 times, meaning the difference is not statistically significant and there is not convincing evidence that one brand is better than the other.

Yes, because a difference in mean rating of 1 point 5 or more occurred only 23 out of 200 times, meaning the difference is statistically significant and there is convincing evidence that cap b is more effective than cap A .

No, because a difference in mean rating of 1 point 5 or less occurred 167 out of 200 times, meaning the difference is not statistically significant and there is not convincing evidence that one brand is better than the other.

Explanation

A difference of 1.5 points or more occurred in 23 of the 200 simulated results, or 23/200 = 0.115 (11.5%). That is not an unusually small proportion, so the observed difference is not statistically significant at the usual 5% level. There is not convincing evidence that either detergent is better.

AI-written and checked against the verified answer.

More from this Course

Practice Test

Practice Test

Test