Six Sigma Formulas and Tables.

[WALLACE]

I am looking for a list of Six Sigma formulas and the explanation of these formulas with sigma and yield tables, Any body help?

Thanks in advance.

Wallace.

 

[Ken K.]

I think you need to be more specific about formulas you're asking for.

I'll give you a few and see if that's what you're asking for:

DPU=Defects/Units

DPMOp=DPMO=PPM=Total 1,000,000*(Defects/Opportunities)

DPMOp=1,000,000*(DPU/Opportunities

SIGMA = SQRT(LN(1/(1-EXP(-DPMOP/1000000))^2))-(2.55155+0.802853*SQRT(LN(1/
(1-EXP(-DPMOP/1000000))^2))+0.010328*SQRT(LN(1/(1-EXP(-DPMOP/1000000))^2))^2)/
(1+1.432788*SQRT(LN(1/(1-EXP(-DPMOP/1000000))^2))+0.189269*SQRT(LN(1/
(1-EXP(-DPMOP/1000000))^2))^2+0.001308*SQRT(LN(1/(1-EXP(-DPMOP/1000000))^2))^3)+1.5

where DPMOP=defects per million opportunities

First Time Yield=
#UnitsPassing1stInspection/#UnitsInspected
approx= e^-DPU

RolledUpYield=
#UnitsCompleteingProcess/#UnitsProcessed
approx= e^(DPU1+DPU2+DPU3...)
where DPU1, DPU2, DPU3 represent the defect rate of process steps 1`, 2, 3, ...

 

[WALLACE]

Thanks Ken k,

I am just getting started in six sigma and, I feel overwhelmed by all of the Mathematical formulas that are used to calculate the most common used functions of six sigma, I guess I need to get familiar with the most commonly used calcualtions.

Wallace.

 

[Greg Mack]

Just take the normal factors for computing central lines and 3 sigma control limits for X-Bar, s and r charts.

A cpk of 2 equals 6 sigma.

That's probably about as basic as it gets.