6.

a. A repeated-measures study with a sample of n 9 participants produces a mean difference of MD 4 with a standard deviation of s 12. Based on the mean and standard deviation you should be able to visualize (or sketch) the sample distribution. Use a two-tailed hypothesis test with .05 to determine whether it is likely that this sample came from a population with D 0.

b. Now assume that the sample standard deviation is s 3, and once again visualize the sample distribution. Use a two-tailed hypothesis test with

.05 to determine whether it is likely that this sample came from a population with D 0.

c. Explain how the size of the sample standard deviation influences the likelihood of finding a significant mean difference.