Question

At 90% confidence interval, is there a difference between the means of Branch 1 and Branch 4?

Given that MSE= 26006.25

	Branch1	Branch2	Branch3	Branch4
	500	500	440	450
	550	700	810	750
	570	340	700	500
	800	710	650	800
sample size	n1=4	n2=4	n3=4	n4=4	ntotal=16
sample mean	x1=605	x2=652.5	x3=650	x4=625	x3=610.625
sample standard deviation	s1=133.291	s2=177.082	s3=155.134	s4=175.594	sG=147.985

1 - The confidence interval is:

2 - The best explanation of the confidence interval result is:

3 - The number of treatments(k) is equal to:

4 - The value of t-critical used in the confidence interval formula is equal to:

5 - The number of observations (n) is equal to:

Answer 1

1. The confidence interval is: (-223.2379, 183.2379).

2. Since the CI contains zero, we are 90% confident that there is insignificant difference between Branch 1 and Branch 4.  

3. k=4

4. Critical value=1.7823.

5. n=16.