Jugal Prasad

Why are you going for such a complicated formula. You have the formula for calculating the DPMO. Use the same formula and goal seek in excel to achieve particular dpmo by changing sigma value. this should suffice your purpose.
All the best.
Jugal
 

Would you please forward the same to me also.
Regards
Jugal
My mail id is : [email protected]

Hi Raj:
If I understand your concern, it seems that you have a confusion over the different formula available. You can use P/T ration to decide the capablity of the gauge if your process is 3 sigma. However, if the process sigma improves the real variation between parts is very small and so inorder to differentiate between the parts your gauge…[Read more]

Hi Sridhar:
I would be delighted if you could send those case studies. My E-mail address is: [email protected]
 
Bye
Jugal

Hi Rajesh:
This is the typical case where directly calculating Cpk is quite complex. Generally when you have one sided tolerance, the data doesnot follow normal distribution. In most of the case it follows poisson distribution. What you do, is calcuate DPMO and from there you calcuate the sigma of the process. Sigma and Cpk can be…[Read more]

Just a suggestion. Whenever you are sampling never develop sampling plan based on AQL only. I find Larsen Nomograph quite useful for developing sampling plan where you have AQL and RQL and the risk you are willing to take for those quality level.
 
Jugal

Not really on absenteeism. Have done similar project on late arrival. If you study the absenteesim in your organisation, it may have different pattern and the pattern would be different for different category of employees. May use Chi Square test to validate and narrow down to the root cause.
Just let me know more about your organisation, I may…[Read more]

If you talk about process capability the Cpk index can be negative not the Cp.

Grateful, if you could send me complete case study.
Thaks

Find variance in transit time of supply of raw material. Stock for only 6 times square root of variance transit time. This will ensure 99.73% up time of the line. Almost no stock out case. This will certainly reduce the inventory.
However, if the variance in the transit time itself is high, just find out the root cause for the same and eliminate…[Read more]

I really doubt that any process may have negative sigma. Yo may have negative process capability. If you really see the DPMO Vs Sigma curve, you have 100% defects, which means each opportunity is defective. Negative sigma, seems to me as defects more than the opportunity.