An Early-Warning Test for Use with the Shewhart p Control Chart

Abstract

A supplementary test for a p control chart consisting of counting the number S of successive occurrences of nonconforming items in a subgroup is given with a table of the probabilities of getting at least S for

subgroup sizes n = 15(5)30, 40, 60, 100

and

binomial p = 0.005, 0.01(0.01)0.06(0.02)0.20, 0.25, 0.30, 0.40, 0.50.

• Runs Test
• Shewhart p Chart

Additional information

Notes on contributors

Lloyd S. Nelson

Dr. Nelson is Director of Statistical Methods. He is a Fellow of ASQC.