The X-bar chart is a control chart which tracks the mean or the average of sub-groups of up to 6 different data points. Although the charts are not as sensitive as the I and MR charts they are very effective and easy to use when looking analyse whether a process is under control or not. The X-bar chart typically is used when monitoring characteristics that can be measured on a continuous basis.
The C&E, XY, Cause and Effect matrix can be used to evaluate the correlation or impact that inputs have on outputs. The tool is most often used to prioritize possible improvements in a project. To learn more about the C&E or XY matrix visit our article entitled The C&E/XY matrix.