Question

Directions: Use the following information to complete the assignment. While APA format is not required for the body of this assignment, solid academic writing is expected, and documentation of sources should be presented using APA formatting guidelines, which can be found in the APA Style Guide, located in the Student Success Center.

A researcher randomly assigns 33 subjects to one of three groups. Group 1 receives technical dietary information interactively from an on-line website. Group 2 receives the same information from a nurse practitioner, while Group 3 receives the information from a video tape made by the same nurse practitioner.

The researcher looked at three different ratings of the presentation; difficulty, usefulness, and importance to determine if there is a difference in the modes of presentation. In particular, the researcher is interested in whether the interactive website is superior because that is the most cost-effective way of delivering the information.

Group	Usefulness	Difficulty	Importance
1	20	5	18
1	25	9	8
1	23	15	20
1	16	9	22
1	20	6	22
1	28	14	8
1	20	6	13
1	25	8	13
1	24	10	24
1	18	10	20
1	17	9	4
2	28	7	14
2	25	14	5
2	26	9	20
2	19	15	22
2	29	14	12
2	15	6	2
2	29	10	5
2	26	11	1
2	22	5	2
2	15	15	14
2	29	6	4
2	15	6	3
3	22	8	12
3	27	9	14
3	21	10	7
3	17	9	1
3	16	7	12
3	19	9	7
3	23	10	1
3	27	9	5
3	23	9	6
3	16	14	22

1. Run the appropriate analysis of the data and interpret the results.
2. How could this study have been done differently? Why or why not would this approach be better?

PLEASE ONLY USING EXCEL OR SPSS. Thank you!

Answer 1

The hypothesis being tested is:

H₀: µ₁ = µ₂ = µ₃

H_a: At least one means is not equal

The output is:

			Factor 2
	Means:
		Usefulness	Difficulty	Importance
	Row 1	22.7	9.7	15.3	15.9
	Row 2	21.3	9.7	17.3	16.1
	Row 3	23.0	8.0	16.7	15.9
	Row 4	21.0	8.7	12.7	14.1
	Row 5	23.3	12.7	15.7	17.2
Factor 1	Row 6	24.3	10.0	6.3	13.6
	Row 7	21.0	10.3	5.7	12.3
	Row 8	22.0	6.7	6.3	11.7
	Row 9	21.7	9.3	7.3	12.8
	Row 10	19.3	8.7	6.7	11.6
	Row 11	22.0	10.7	11.0	14.6
		22.0	9.5	11.0	14.2
	3	replications per cell
ANOVA table
Source	SS	df	MS	F	p-value
Factor 1	341.39	10	34.139	1.13	.3511
Factor 2	3,063.52	2	1,531.758	50.89	4.26E-14
Interaction	445.15	20	22.258	0.74	.7713
Error	1,986.67	66	30.101
Total	5,836.73	98
Post hoc analysis
p-values for pairwise t-tests for Factor 2
		Difficulty	Importance	Usefulness
		9.5	11.0	22.0
Difficulty	9.5
Importance	11.0	.2660
Usefulness	22.0	1.61E-13	1.60E-11
Tukey simultaneous comparison t-values (d.f. = 66)
		Difficulty	Importance	Usefulness
		9.5	11.0	22.0
Difficulty	9.5
Importance	11.0	1.12
Usefulness	22.0	9.24	8.12
critical values for experimentwise error rate:
		0.05	2.40
		0.01	3.02

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 is a difference in the modes of presentation.

The interactive website is not superior because the p-value (0.7713) is less than the significance level (0.05).