Statistics: Principles and Methods, 7th Edition

10

Comparing Two Treatments

1 Two Designs: Independent Samples and Matched Pairs Sample

2 Inferences about the Difference of Means—Independent Large Samples

3 Inferences about the Difference of Means—Independent Small Samples from Normal Populations

4 Randomization and Its Role in Inference

5 Matched Pairs Comparisons

6 Choosing between Independent Samples and a Matched Pairs Sample

7 Comparing Two Population Proportions

Are video game playing skills transferable?

Does Playing Action Video Games Modify Ability to See Objects?

Video game playing is now a widespread activity in our society. Two scientists¹ wondered if the game playing itself could alter players' visual abilities and improve performance on related tasks. As one part of their experiment, they briefly flashed different numbers of target squares on the screen. The count of the number of target squares flashed that could be unerringly apprehended was recorded for a sample of 13 regular game players and 13 nonplayers. (courtesy of G. Green).

The difference in sample means, 4.89 − 3.27 = 1.62 items apprehended, is substantial. A 95% confidence interval for the difference of population means is

With 95% confidence we ...