Batch number, revision number, and the value for percent solids are included. If the batch passed without rework, the revision number is 1. If one rework cycle was required, the batch revision number is 2 and so on, for additional revisions until the value is in specification. Specifications for percent solids for this product are 55 0.5. Only when a process is operating with a predictable behavior can a statement be made about the quality of the untested product.
Current data show that some samples contained defective units.
This makes it unlikely that the rest of the shipment is free of defective units. There are two related problems in these data. One is the problem of expressing counts of defective units as rates in DPM when only 500 to 1,000 units are tested. In such situations, there is a perceived level of detail in the data that does not exist. The second problem occurs when the true level of detail in the data, of which one may be unaware, is not small enough to obtain a correct estimate of the standard deviation of the process.