Lot Sampling Plans Module 22 (single & double):
DfRSoft provides two types of automated lot sampling
plans : Hypergeometric
method (N, n, c) where N is the lot size, n is the sample from
the lot, and c is the number of sample(s) that are allowed
before the entire lot is rejected and the Binomial method (n, c)
"N not used". Two key values, AQL (Acceptable Quality Level),
and LTPD (Lot Tolerance Percent Defective) values. OC Binomial
and Hypergeometric lot curves plotting Probability of Acceptance
vs. Lot Percent Defective (AOQ). Select N, n, c and AIQ obtain
AQL and LTPD, and AOQ with confidences. This makes MIL-STD 105E
or ANSI/ASQ Z1.4
Standards on Lot Sampling look easy and is much more flexible.
Sometimes we are not sure about a lot and we would like to do
more inspection or we may wish to take a risk and sample less
but decide that if we do this and exceed a certain criteria, we
might do a second sampling to decide whether or not to accept or
reject a lot. In addition to the single sampling, an example is
provided on using this tool for Double sampling which can
actually reduce the number of single samples taken.
SEE
DfRSoft LOT SAMPLE PLAN VIDEO