The Bias Comparison option creates an Analysis of Means chart. This chart shows the mean values for each level of the grouping variables and compares them with the overall mean. You can use this chart to see whether an operator is measuring parts too high or too low, on average.
The red triangle menu next to Analysis of Means contains the following options:
Set Alpha Level
Select an option from the most common alpha levels or specify any level using the Other selection. Changing the alpha level modifies the upper and lower decision limits.
Show Summary Report
Shows a report containing group means and decision limits, and reports if the group mean is above the upper decision limit or below the lower decision limit.
Display Options
Include the following options:
Show Decision Limits
Draws lines representing the Upper Decision Limit (UDL) and the Lower Decision Limit (LDL) and defines those values.
Show Decision Limit Shading
Adds shading between the UDL and the LDL.
Show Center Line
Draws the center line statistic that represents the average.
Point Options
Changes the chart display to needles, connected points, or points.