The u chart for monitoring [lambda], the average number of defects per inspection unit, requires [lambda] to be large to have positive lower control limits, and the false alarm probabilities differ considerably from the nominal normal values. Based on nonlinear transformations, some alternative...

In this paper a simple and efficient algorithm for obtaining the critical values of t, [chi]2 and F distributions is proposed. They depend only on a direct iterative rational function. The differences between the proposed algorithm and others are discussed.