Question

2.

Clark Heter is an industrial engineer at Lyons Products. He would like to determine whether there are more units produced on the night shift than on the day shift. The mean number of units produced by a sample of 53 day-shift workers was 355. The mean number of units produced by a sample of 62 night-shift workers was 363. Assume the population standard deviation of the number of units produced on the day shift is 24 and 32 on the night shift.

At the 0.01 significance level, is the number of units produced on the night shift larger?

1. Is this a one-tailed or a two-tailed test?

• One-tailed test or Two-tailed test

2. State the decision rule. (Negative value should be indicated by a minus sign. Round your answer to 2 decimal places.)

3. Compute the value of the test statistic. (Negative value should be indicated by a minus sign. Round your answer to 2 decimal places.)

4. What is your decision regarding H₀?

• Reject H₀. or Do not reject H₀.

Answer 1

Day-shift Worker:

n1 = 53, = 355, 1 = 24

night-shift Worker:

n2 = 62, = 363, 2 = 32

a) One tailed (left tailed test)

a)

Test statistic < Critical value, then Reject Ho at 1% level of signfiicance.

b)

Hypothesis:

Ho: 1 = 2

Ha: 1 < 2 OR more units produced on the night shift than on the day shift

Test statistic:

Critical value:

Z = Z 0.01 = -2.33 ................Using standard Normal Table

C)

Test statistic > Critical value, i.e. -1.53 > -2.33, That is Fail to Reject Ho at 1% level of significance.

Therefore, there is Not sufficient evidence to conclude that, the more units produced on the night shift than on the day shift.

ANSWER: B

DO not reject Ho