cpk value

[toineke]

Can I calculate in Excel statistics the cpk value??

 

[bobhc]

Good day toineke


A quick walk through


1


Launch Microsoft Excel and type “Data” in A1, “Upper Limit” in B1, “Average” in C1, “StDev” in D1, and “Cpk” in E1.


2


Type “1” in A2, “2” in A3, “3” in A4, “4” in A5, “5” in A6, “6” in A7, “7” in A8, “8” in A9, “9” in A10, and “10” in A11. Type “15” in B2.


3


Add the following formula in C2 to calculate the average for the data:


=AVERAGE(A2:A11)


4


Add the following formula in D2 to calculate the standard deviation for the data:


=STDEV(A2:A11)


5


Calculate CPK using the upper limit, average, and standard deviation values by adding the following formula in E2:


=((B2-C2)/(3*D2))

 

[toineke]

thanks but


A colleague used Minitab (an statistic program compatibel with excel, but very complex in use)

And I use Excel 2010 and there is a significant diference in results of the example

Average is the same (5.5)

Stdev 3,11276 (MT) instead of 3,02765 (Excel)

CpK 1,02 (MT) instead of 1,0459156 (Excel)


I known and understand that there are more possiblities for STDEV in excel 2010 (Stdev.P ; Stdev.S; stdeva and stdevpa)


But I cant explain the different results in Minitab and Excel.

especially the cpk value.