Two machines C1 and C2 are making pins which must have a dia

Two machines, C1 and C2, are making pins which must have a diameter of 8 cm .01 cm or they are rejected. Dotplots of 50 pins from each machine are displayed below. They are both on the same scale. By simply looking at the dotplots, i.e. without doing any calculations or counting, compare the distributions of the two machines: In what sense is machine Cl ^\'better6^\' at producing pins? Justify your argument.

Solution

From distribution, machine 2 is better because almost all its poitns are within 0.01 cm of 8, whereas in C1, more points lie outside this acceptance range. Thus C2 is more precise. Further, C2 has a nice peak very near to 8 cm (target), wheras C1 is bimodal, implying that C1 is not caliberated correctly, and that C2 is more accurate.