List of Procedures
Policy and General: STAT01 is the general policy procedure and STAT02 provides definitions used by the procedures.
STAT01 Statistical Policy
STAT02 Glossary of Statistical Terms
Areas of Application: STAT03 to STAT11 describe the statistical requirements for each area of application. They may also provide statistical techniques that are specific to that area of application or reference a supporting statistical technique procedure.
STAT03 Statistical Techniques for Process Validation
STAT04 Statistical Techniques for Design Verification
STAT05 Statistical Techniques for Component/Material Qualifications
STAT06 Statistical Techniques for Design Validation
STAT07 Statistical Techniques for Audits and Effectiveness Checks
STAT08 Statistical Techniques for Test Method Validation
STAT09 Manufacturing Acceptance Sampling Plans and Inspections
STAT10 Statistical Techniques for Trending Data
STAT11 Statistical Techniques for Setting Specifications
Supporting Statistical Techniques: STAT12 to STAT19 describe specific statistical techniques. They do not specify any additional requirements beyond those in the policy and application procedures.
STAT12 Verification/Validation Sampling Plans for Proportion Nonconforming
STAT13 Verification/Validation Sampling Plans for Rate of Nonconformities
STAT14 Verification/Validation Sampling Plans for Average
STAT15 Verification/Validation Sampling Plans for Standard Deviation and RSD
STAT16 Statistical Techniques for Equivalence Testing
STAT17 Statistical Techniques for Reliability Life Testing
STAT18 Statistical Techniques for Normality Testing and Transformations
STAT19 Rounding of Data
Errata
Changes in Second Printing from First Printing
STAT09 Manufacturing Acceptance Sampling Plans and Inspections
Table 3 on page 140, changed as follows:

 For Moderate Process Risk:

 From: RQL up to 12 times the AQL (Appendix A: L5 to L13)
 To: RQL up to 9 times the AQL (Appendix A: L6 to L13)

 For Low Process Risk:

 From: RQL up to 45 times the AQL (Appendix A: L1 to L13)
 To: RQL up to 16 times the AQL (Appendix A: L4 to L13)
This change results in better aligning STAT08 with ANSI Z1.4 and ISO 28591. For an AQL of 1.0%, Z1.4 has the plans 13/(0,1), 50/(1,2), 80/(2,3), 125/(3,4), 200/(5,6), … With this change low process risk is 13/(0,1), moderate process risk is 50/(1,2) and high process risk is 125/(3,4).
Previously, low process risk was 5/(0,1) with an RQL of 36.9. Some consider this too little protection. Designers of Z1.4 wrestled with whether to fix the probability of acceptance at the AQL at 95% or let it vary. 5/(0,1) has an AQL of 1.0, while 13/(0,1) has an AQL of 0.4%. They let it vary going with the plan 13/(0,1). While my tables fix the probability of acceptance at the AQL at 95%, this change has the same effect of avoiding the 5/(0,1) plan.
Consider this change as a suggestion that may be appropriate for some but not all readers.
Errata for both Second and First Printing
Multiple occurrences of the word gage should be replaced with gauge.
STAT02 Glossary of Statistical Terms
Page 24, under definition for Distribution function, “average of 7” should be “average of 10.”
STAT03 Statistical Techniques for Process Validation
Pages 35, 38 and 48, “OC characterization” should be “OQ characterization”
STAT06 Statistical Techniques for Design Validation
Page 78, two occurrences of nonconforming should be conforming.
STAT08 Statistical Techniques for Test Method Validation
Page 119, the guardband equations are in error and should read as shown below.
Lower guardband limit = LSL + Max_{bias} + K x UCL_{σguardband}
Upper guardband limit = USL + Min_{bias} – K x UCL_{σguardband}
STAT12 Verification/Validation Sampling Plans for Proportion Nonconforming
Page 360, for 95/90 Variables—OneSided Specification the P_{pk} acceptance criterion for n=15 can be reduced from 0.70 to 0.69.
STAT18 Statistical Techniques for Normality Testing and Transformations
Page 570, Section 6.1 should say: “For a single normality test, the test is
considered to pass if the pvalue is > 0.05.”
Errata for First Printing Corrected in Second Printing
They have been corrected in the current second printing.
Table of Content and elsewhere
STAT10 title has “tending” rather than “trending”.
Introduction
Table 1 of page 3. RNP should be RPN.
STAT02 Glossary
Page 25, kurtosis, as defined here, is sometimes referred to as the excess kurtosis and is the statistical kurtosis minus 3.
STAT08 Statistical Techniques for Test Method Validation
Page 101, the reference in Section 6.3.2 to Section 6.3 should be a reference to Section 6.3.1.
STAT09 Manufacturing Acceptance Sampling Plans and Inspections
Page 142, Example box should give n=80, a=2 as the “also use” sampling plan rather than n=80, a=3.
Page 162, the AQL=10%, L3, Variables Single, σ unknown plan is in error. Change MSD to 333.3%.
Page 173 the AQL=1%, L8, Variables Single, σ unknown plan is in error. Change MSD to 22.5%.
STAT10 Statistical Techniques for Trending
Page 200, the last sentence should reference Appendix I and not Appendix J.
Page 214 the equations for the control limit should be as shown below.
Page 233 the equations for the control limits of the I_{N} chart should be as shown below.
Page 247, bottom right, 0.000502 should be 0.000557.
STAT13 Verification/Validation Sampling Plans for Rate of Nonconformities
Page 424 makes reference to the Beta distribution. It should have referenced the Gamma distribution. There are also some formatting issues.
STAT15 Verification/Validation Sampling Plans for Standard Deviation and RSD
Page 471 shows screenshots for 95% confidence rather than the 90% confidence stated in the text. The confidence statements given in the text are correct but do not align with the graphic.
Page 472 shows formulas for the confidence intervals for the standard deviation. These formulas use the CHIINV function in Excel, which returns the inverse of the righttailed chisquared distribution function. These are the formulas used in the spreadsheet. For the more common inverse of the lefttailed chisquared distribution function, reverse the formulas for the upper and lower confidence limits.
STAT17 Statistical Techniques for Reliability Life Testing
Page 530, the last two paragraphs of the example should read:
To select a plan, use Appendix B of STAT13. The ratio RQL/AQL = 4. The
resulting single sampling plan is n = 11.8424/RQL, a = 6. Plugging 2 in for the RQL
results in n = 5.9212. This can be rounded up to n = 6 years.
It is desired to complete the testing within 6 months. This requires testing 12 pumps
for half a year to produce 6 years of test time. If 6 or fewer service events occur,
the sampling plan passes, and it can be stated with 95% confidence that the rate of
service events is below 2 per year.
Page 531, the same changes should be made to the last two paragraphs of the example.
STAT18 Statistical Techniques for Normality Test and Transformations
Page 565 if states Z_{k} is valid for n≥20. Simulations demonstrate it is valid for n≥15.