National Computer Products Inc NCP manufactures printers and

National Computer Products, Inc (NCP) manufactures printers and fax machines at plants in Charlotte,Houston,and San Diego.To measure how much employees at these plants know about total quality management,a random sample of employees was selected from each plant and given a quality -awareness examination. The examination scores obtained for the employees and ANOVA A result are listed below.Use the output to answer the following questions at the 0.05 significance level

Analysis of Varience for Quality Awareness

Source     DF     SS           MS       F             P

Plant        2        516.0      258.0    9.00        0.003

Error       15        430.0       28.7

Total       17        946.0

Indivividual 95% Cls For Mean

Based on Pooled StDev

Level           N       Mean      StDev ------+-----------+----------------+-------------+----

Plant 1        6    79.000      5.831                    (-------------)

Plant 2     6       74.000       4.472            (------------)

Plant   3    6          66.000    5.657 (--------)

                                     ------+-----------+-----------+-------+------

Pooled StDev = 5.354      63.0    70.0 77.0   84.0

Which of the following is a false statement?

A. Reject the null hypothesis at alpha = .004

B. There is a difference between and within a group variance

C. The variance among the groups appears to be the same

D. MS within plus MS between equal MS total.

E. The statistical test chosen for this problem is valid

Solution

All options are correct, except

OPTION C: The variance among the groups appears to be the same. [ANSWER]

As we can see, the variation between groups is significantly different to the variation within groups.