Question

1. In order to find the best method to teach statistics, Dr. Nelson used strictly power point slides, white board with black markers, and a white board with color markers for his three different classes. His main objective was to compare exam scores in the three different classes. The results were as follows:

Class	Exam Score	Class	Exam Score	Class	Exam Score
1	87	2	87	3	89
1	86	2	85	3	91
1	76	2	99	3	96
1	56	2	85	3	87
1	78	2	79	3	89
1	98	2	81	3	90
1	77	2	82	3	89
1	66	2	78	3	96
1	75	2	85	3	96
1	67	2	91	3	93

1. State the null and research hypothesis.

2. Calculate the F value by hand using a source of the variance table.

           

3. What is the interpretation of the critical value compared to the observed value at .05 level of significance?
4. What is the conclusion for α = .05? Write up the results at p = .05 in APA format using the SSPS output below:

(I). Group	(J) Group	Mean Difference	Significance	Different?
PowerP’s	Black Markers	-8.60	.071
PowerP’s	Color Markers	-15.00	.001
Black Markers	Color Markers	-6.4	.257

5. What is the value of ω² & ε² and what do both the effect sizes tell us?

Answer 1

To test the null hypothesis

ie The three teaching methods yields the same score or there is no difference in the teaching methods

against the alternative that atleast one method differ from the others

An ANOVA test has been conducted to test the above hypothesis and the table is given below

F value is calculated using the formula =MS between/MS within=566.533/64.385=8.799

The pvalue tells us to reject the null hypothesis at 5% significance level . since p value <0.05

Also the F value > F critical value which again directs us to reject the null hypothesis

(I). Group	(J) Group	Mean Difference	Significance	Different?
PowerP’s	Black Markers	-8.60	.071	NOT Different
PowerP’s	Color Markers	-15.0	.001	Different
Black Markers	Color Markers	-6.4	.257	NOT Different

power point and color markers are statistically significant at 5% significance level.