Sec. 5.6 CONTROL CHARTS 147 



observed fraction defective will tend to increase rather soon, although 

 it might not do so for several samples; and (£>) the variability among 

 samples will increase if p changes toward 1/2, and this is the case 

 cited above. Both these points are illustrated by means of Table 

 5.61 and Figure 5.61. 



TABLE 5.61 



Samples with n = 50, p Starting at .05 and Increasing .002 per Sample 



from the Twenty-sixth to the Seventy-fifth Samples, Inclusive, After 



Which It Remains at .15 



Sample Fraction Sample Fraction Sample Fraction 



Number Defective Number Defective Number Defective 



