2.

A cement manufacturing company has a packing plant containing a large number of packing machines. To test the consistency of packing performance across machines, three machines (denoted by M/C 1, M/C 2, and M/C 3) were selected from the plant, and 20 bags (each supposed to be of weight 50 lb) were filled in each of the three machines. The data (courtesy of T. Dasgupta) in Table 2.10 indicate the actual weight (in pounds) of each of the 60 bags.

(a) Suppose the interest lies in the comparison of the three chosen machines in the plant. Analyze the data using one-way layout with fixed effects. Your work should include ANOVA and F test.

(b) What can you conclude from (a)?

Table 2.10 Packing Machine Data

M/C 1	M/C 2	M/C 3
49.89	50.69	49.36
48.8	51.5	49.92
49.22	52.09	49.52
49.34	50.87	50.22
48.77	50.69	50.23
48.71	51.05	49.78
50.06	51.6	48.67
49.51	50.69	49.98
49.11	50.48	50.86
49.98	51.13	50.51
49.64	51.16	48.95
48.91	51.49	49.85
50.3	50.84	49.49
49.67	51.11	49.29
50.39	50.94	49.16
50.18	51.15	50.07
49.09	52.12	49.64
48.72	50.84	49.93
49.46	50.39	49.68
49.3	51.48	49.62