A Nonparametric Change-Point Control Chart
نویسندگان
چکیده
I N STATISTICAL process control (SPC), one major concern is whether there has been a change of the distribution from the target in the process. To answer this question, we have to distinguish the variation due to real change of distribution (assignable causes) from that due to random error (chance causes). Many kinds of control charts serve this purpose. When there is no change and the process is in control, the probability of a false signal from the chart should be controlled at a low and known false-alarm rate. And when there is some change and the process is out of control, a good chart should detect it as soon as possible. The performance of a chart is usually measured by average run length (ARL)—the expected number of samples or subgroups to be collected before the first signal.
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