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Publication date: 11/10/2021

Bias Comparison

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.

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