Question

Recent research indicates that the effectiveness of antidepressant medication is directly related to the severity of the depression (Khan, Brodhead, Kolts & Brown, 2005). Based on pretreatment depression scores, patients were divided into four groups based on their level of depression. After receiving the antidepressant medication, depression scores were measured again and the amount of improvement was recorded for each patient. The following data are similar to the results of the study.

Low Moderate	High Moderate	Moderately Severe	Severe
1.2	2.6	2.6	2.3
2.2	2.5	0.7	0.8
1.8	1.9	2.3	3.2
0.5	1.8	3.3	3.8
0	3.4	1.5	1.7
2.8	1.6	3.1	1.6
2.4	0	1.6	5.4
2.9	1.8	1.1	3.1
3	1.2	2.4	2.6
2.6	3.5	1.2	1.3
0.9	3.5	2.6	2
1.7	1.7	0.2	3
2	0.5	3.7	1.8
2.3	2.9	2.1	4.7
2.4	0.3	1	2.6
1.6	1.2	2	2
2.7	2.3	3.3	1.8
2.9	1	0.2	3.6
0.3	2.1	3.4	2.5
1.6	2.6	0.8	2.3
3	1.7	1.1	2.3
2.6	3.2	1.6	2.9
2.9	3.7	2.7	3.7
2.7	2.5	0.9	1.6
2.2	1.7	3.2	2.6
1.5	1.5	2.5	3.1
2.9	1.7	1.5	3
2.4	2.6	3.4	1.7
1.5	1.7	2.8	2.4
1.6	1.7	2.3	5.9
3.2	3.3	1.5	3.1
2.4	0.8	2.4	0.7
1.9	2.8	3.2	2.3
1.7	3.9	1	1.8
2.1	2.4	1.7	3.2
2.5	1.5	2.3	3.3
3.9	3.1	1.1	1.8
3.7	1.4	2.1	3.3
1	0.6	0.5	2.9
2.3	3.4	1.2	2.4
1.1	4.3	2.1	1.2
1.7	2.8	1.7	1.5
4.3	2.9	3.4	3.4
2.2	2.3	1.3	2.9
2.5	0.3	3.5	2.9
1.5	1.4	1.3	3.2
1.5	2.6	2.4	3.6
2.8	2.1	1.6	3.3
1.6	1.9	0.6	2.7

This is the summary table for the ANOVA test:

	S.S.	d.f.	M.S.
Between	13.944489795918	3	4.6481632653061
Within	181.01795918367	192	0.9428018707483
TOTAL	194.96244897959	195

From this table, you obtain the necessary statistics for the ANOVA:
F-ratio: 4.9301591453323
p-value: 0.00254
η2= 0.071523977406429

What is your final conclusion? Use a significance level of α=0.02

• There is a significant difference between treatments
• These data do not provide evidence of a difference between the treatments

Explain what this tells us about the equality of means.

Answer 1

Answer:-

Thanks dear student ?