Question

A pharmaceutical company is testing a new drug to increase memorization ability. It takes a sample of individuals and splits them randomly into two groups. One group is administered the drug, and the other is given a placebo. After the drug regimen is completed, all members of the study are given a test for memorization ability with higher scores representing a better ability to memorize. You are presented a 90% confidence interval for the difference in population mean scores (with drug - without drug) of (-21.3, -10.59). What can you conclude from this interval

1)	We do not have enough information to make a conclusion.

2)	We are 90% confident that the difference between the two sample means falls within the interval.

3)	There is no significant difference between the average memorization abilities for those on the drug compared to those not on the drug.

4)	We are 90% confident that the average memorization ability of those on the drug is higher than those who are not on the drug.

5)	We are 90% confident that the average memorization ability of those not on the drug is higher than those who are on the drug.

Answer 1