2. Automated testing and inspection technology allow measurement of every unit produced.
In these cases, also consider the cumulative sum control chart and the exponentially
weighted moving average control chart discussed in Chapter 9.
3. The data become available very slowly, and waiting for a larger sample will be
impractical or make the control procedure too slow to react to problems. This often
happens in nonproduct situations; for example, accounting data may become available
only monthly.
4. Generally, once we are in phase II, individuals charts have poor performance in shift
detection and can be very sensitive to departures from normality. Always use the
EWMA and CUSUM charts of Chapter 9 in phase II instead of individuals charts
whenever possible.