In control chart logic, what is the term for the limits based on your desired level of process confidence?

In control chart logic, the limits that are established based on the desired level of process confidence are referred to as confidence limits. These limits define the expected range of variability in the process over time, indicating whether a process is in control or out of control.

When setting these limits, statistical methods are applied to determine the appropriate range, ensuring a desired level of confidence (usually expressed in terms of standard deviation) for monitoring the process performance. By doing so, businesses can better assess whether changes to the process are within acceptable parameters or indicative of potential problems.

The other terms do not accurately capture this concept. "Target" typically refers to a goal or desired outcome, "variability" relates to the extent of variation observable in the process but does not imply limits, and "quality" refers to the overall standard or degree of excellence of the process outcome rather than specifically focused on statistical limits.