The times in minutes to assemble a computer component for 3

The times (in minutes) to assemble a computer component for 3 different machines are listed in the table below. Workers are randomly selected.

Machine1   

Machine 2

Machine 3

32

35   

28

30

29

25

31

38

29

32

33

31

34

32

29

35

36

a)   Assuming all conditions are met, test the claim that there is a difference in mean assembly time for each machine using a 5% level of significance. Use the P-value approach.

b)   What provides visual support for your decision in part (a)? Explain.

Please use the P-value Approach for all hypothesis tests. Follow all the steps used in hypothesis testing

Solution

Set up hypotheses as

H0: All machines take equal assembling time

Ha: Atleast two take different time

Alpha = 0.05

Let us prepare anova table and check.

p value = 0.00668

As p value >0.05, accept null hypothesis.

Mean for all are near the overall mean.