## Economical quality control procedures based on symmetric random walk model.(English)Zbl 0843.62100

Summary: Assuming the quality characteristic process follows a symmetric random walk model, the on-line control procedure is studied without the assumption of normality. Simple approximations for the long run average cost rate and the optimal control parameters are provided. In particular, the robustness of the on-line control procedure under the mixed normal random walk model is demonstrated.

### MSC:

 62P30 Applications of statistics in engineering and industry; control charts 60G50 Sums of independent random variables; random walks