Question

3. A researcher is interested in the effects of alcohol consumption on an individuals’ ability to maintain their balance. She decides to test college students by having five groups drink five different amounts of alcohol and test them to see how many times they fall during a balancing task. In the first group subjects do not drink any alcohol, the second group drinks one 3 oz. glass of 100 proof alcohol in one half hour, the third group drinks two 3 oz. glasses of 100 proof alcohol in one half hour, the fourth group drinks four 3 oz. glasses in one half hour, and the fifth group drinks eight 3 oz. glasses of 100 proof alcohol in one half hour. Her data are reproduced below; each score represents number of errors for each of her subjects during the balance task.

Group 1 0 drinks	Group 2 1 drink	Group 3 2 drinks	Group 4 4 drinks	Group 5 8 drinks
1	3	4	10	12
2	1	1	4	13
1	6	7	9	9
3	5	5	8	16
4	7	8	6	17
2	6	5	11	11
2	8	6		8
4				10

1. Carry out a one-way ANOVA to test the effects of these variables in this experiment. Create and record your calculations in the ANOVA table. (6 points)

2. From these analyses, what do we know about the effects of amount of alcohol on students’ ability to balance? Be sure to include a discussion of the critical value in your answer (1.5 points)

Answer 1

(a)

Source	SS	df	MS	F	p-value
Treatment	417.38	4	104.346	17.81	1.09E-07
Error	181.59	31	5.858
Total	598.97	35

(b) The hypothesis being tested is:

H0: µ1 = µ2 = µ3 = µ4 = µ5

Ha: At least one means is not equal

The p-value is 0.0000.

Since the p-value (0.0000) is less than the significance level (0.05), we can reject the null hypothesis.

Therefore, we can conclude that there are effects of the amount of alcohol on students’ ability to balance.