Question

A researcher wishes to determine if the use of iPads improves memory. Subjects will use the iPad regularly during a 10-week period of time. After this ten-week period, each subject has their memory tested using a standard memory test. Suppose the scores on this test of memory for all potential subjects using iPads follow a Normal distribution with mean μ and standard deviation σ = 6. Suppose also, that in the general population of all people, scores on the memory test follow a Normal distribution, with mean 50 and standard deviation σ = 4. The researcher, therefore, decides to test the hypotheses

H₀: μ = 50, H_a: μ > 50

To do so, the researcher has 100 subjects follow the protocol described above (using iPads regularly for a 10-week period). The mean score for these students is 55.2 and the P-value is less than 0.0001.

It is appropriate to conclude which of the following?

Question 13 options:

	None of the answers are correct
	The researcher has conclusively proved that the regular use of iPads improves memory.
	The researcher has strong evidence that people that use iPads regularly, on average, have higher memory test scores than those that don't use iPads regularly. However, the difference may or may not be important.
	The researcher has strong evidence that regular use of iPads improves memory, and because the P-value is so small, the difference must be substantial.

Answer 1

Since P-value < 0.0001, so we reject the null hypothesis.

Conclusion :

The researcher has strong evidence that regular use of iPads improves memory, and because the P-value is so small, the difference must be substantial.