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#### unueco

I'm am looking for a bit of technical/theoretical background concerning acceptance sampling plans.

Almost from my first day on the job working in QA, I've had various "gurus" in the field tell me not to use any of the standard sampling plans (ISO 2859-1, ANSI/ASQ Z1.4, mil std 1916, etc etc). No instead the true QA practitioner should develop his/her own specific sampling plan based on desired probabilities of acceptance based on fractional lot defective using something like a Larson Nomograph.

I thought I understood. But I'm finding the more I read on this, the more confused I am getting.

For example:

Most standard plans have "Lot size" as an input parameter. But its is not a parameter for Larson's. Is this because Larson's is based on the use of a binomial distribution -- which itself is based on an assumption of an infinite lot size? If so, then doesn't the accuracy of this approach depend on having "large" lots sizes? Is one better off using the standard tables for smaller lot sizes? And just how big is big anyway??

Conversely, Mil-std 1916 specifically states that it is designed to be used *in lieu of* "

*AQL based sampling plans*". How does that work?

So...as I said...I'm a bit confused.

Any assistance, guidance, or pointers to reference sources is highly appreciated!

Thanks!