100-Metodos-de-Qualidade-Total

172 100 METHODS FOR TOTAL QUALITY MANAGEMENT
Example
Figure 1 shows a dot plot of a process yield of ten runs in a chemical plant.
66 77 68 69 71 70 72 73 62 75 (sample)
Figure 2 shows the composition of two samples of a process yield from a
chemical plant by dot plots.
Sample 1: 72 71 73 76 74 77 69 80 68 79
Sample 2: 72 74 79 73 71 67 78 77 80 65
I Here we see that the averages of the two samples are about the same, but
sample 1 has less variation than sample 2.
Reference
P.W.M. John (\990) Statistical Methods in Engineering and Quality Assurance. New York:
Wiley.