Question

The postal service sorts mail as Priority Mail Express, Priority Mail, First-Class Mail, or Standard Mail. Over a period of 3 weeks, 18 of each type were mailed from the Network Distribution Center in Atlanta, Georgia, to Des Moines, Iowa. The total delivery time in days was recorded. Minitab was used to perform the ANOVA. The results fSouyrc

Source	DF	SS	MS	F	P
Factor	3	2.67	0.89	3.07	0.034
Error	68	19.43	.29
Total	71	22.10

Level	N	Mean	StDev
Priority Mail Express	18	2.928	0.622
Priority Mail	18	3.252	0.583
First Class Mail	18	3.468	0.439
Standard Mail	18	3.193	0.473

1. What is the decision rule? Use the 0.01 significance level. (Round your answer to 2 decimal places.)

Answer 1

At alpha = 0.01 L.O.S , df = ( 3,68 )

f critical value = 4 .08

So

Decision rule is : Reject null hypothesis ( H0 ) if F > 4.08

F cal < f crit

i.e., 3.07 < 4.08

Conclusion : so fail to reject H0