# Methods and formulas for the Analysis Of Main Effects (ANOME) chart in Evaluate Measurement Process (EMP Crossed)

The Analysis Of Main Effects (ANOME) chart has a reference line at the overall average and plots the averages of the measurements by each operator. The chart includes decision limits that test for operator bias. The decision limits use the following formulas:

Upper Decision Limit (UDL)
+ ×
Lower Decision Limit (LDL)
×
In the equations, is the ANOME alpha scale factor. This factor has the following equation:

## Notation

TermDescription
the overall mean of the measurements
the average range
The positive, two-sided critical value from the t distribution for /2. By default, = 0.05.
The unbiasing constant from Appendix C 1. When looking for this value, use g = (# of parts) * (# of operators) and m = (# of replicates).
nthe number of measurements by one operator
1 Automotive Industry Action Group (AIAG) (2010). Measurement Systems Analysis Reference Manual, 4th edition. Chrysler, Ford, General Motors Supplier Quality Requirements Task Force