What is a "Control Chart" used for in Six Sigma?

A Control Chart is an essential tool in Six Sigma used to monitor process variability over time. This statistical process control tool helps identify trends, shifts, or any unusual patterns that may indicate a change in the performance of a process. By plotting data points over time against control limits, analysts can determine whether a process is stable and in control or if it requires investigation and corrective action.

The primary function of a Control Chart is to provide insight into the consistency and predictability of a process, enabling practitioners to maintain the quality of their output. For example, if the points on the chart fall outside of the control limits, it signals that there is a significant variation that requires attention, which could indicate the presence of a special cause of variation rather than a common cause.

Other options do not align with the primary purpose of a Control Chart. While displaying the frequency of defect types pertains to understanding quality levels, it does not reflect ongoing process performance over time. Setting production schedules relates to resource planning and optimization, which is distinct from the monitoring of process stability. Evaluating employee performance involves metrics related to individual output and efficiency, not process control and variability. Thus, the correct utilization of a Control Chart is clearly focused on monitoring and analyzing process behavior through time, which is