Feature Addition: I Chart and Laney P’ Chart
User Benefit
The Individuals chart improves readability of individual type data that was previously only available using an I-MR Chart. The Laney P’ chart allows users to create attributes charts that adjust for overdispersion or underdispersion.
Summary
Use an Individuals chart (I chart), to monitor the mean of your process when you have continuous data that are individual observations that are not in subgroups. Use this control chart to monitor process stability over time so that you can identify and correct instabilities in a process.
Use a Laney P’ chart to monitor the proportion of defective items that are produced by your process and to adjust for overdispersion or underdispersion in your data. Overdispersion can cause a traditional P chart to show an increased number of points outside the control limits. Underdispersion can cause a traditional P chart to show too few points outside of the control limits. The Laney P’ chart adjusts for these conditions. For more information, go to Overdispersion and underdispersion.
Feature Addition: Control Chart Stages
User Benefit
Stages allow users to display multiple process changes over specific periods of time on a single control chart.
Summary
Use stages to create a historical control chart that shows how a process changes over specific periods of time. Stages make it easy to communicate process changes and shifts in process behavior within a single visualization. By default, control charts recalculate the center line and control limits for each stage.
