8a.Compute Cohen's d to estimate the size of the effect (MUST SHOW WORK FOR THIS PROBLEM).

Note:Use theprompt provided in 6a &7a for this problem.

Prompt 6a) In a study examining the effect of alcohol on reaction time,Liguoriand Robinson (2001) found that even moderate alcohol consumption significantly slower response time to an emergency situation in a driving simulation. In a similar study, researchers measured reaction time 30 minutes after participants consumed one 6-ounce glass of wine. Again, they used a standardized driving simulation task for which the regular population averages = 400 msec. The distribution of reaction times is approximately normal with= 40. Assume that the researcher obtained a sample mean ofx = 422 for then= 25 participants in the study.

Are the data sufficient to conclude that the alcohol has a significant effect on reaction time? Use a two-tailed test with= .01.

Prompt 7a) In a study examining the effect of alcohol on reaction time,Liguoriand Robinson (2001) found that even moderate alcohol consumption significantly slower response time to an emergency situation in a driving simulation. In a similar study, researchers measured reaction time 30 minutes after participants consumed one 6-ounce glass of wine. Again, they used a standardized driving simulation task for which the regular population averages= 400msec. The distribution of reaction times is approximately normal with= 40. Assume that the researcher obtained a sample mean ofx = 422 for then= 25 participants in the study.

Does the data provide evidence that the alcohol significantly increased (slowed) reaction time? Use a one-tailed test with= .05.

8b.Would the effect size calculated in 8a be considered a small, medium, or large effect?

a) Small

b) Medium

c) Large

d) No effect