Statistical basis and justification while comparing / changing sampling plans

Elsmar Forum Sponsor

Bev D

Heretical Statistician
Staff member
Super Moderator
#12
Welcome Mai.

Your question, while simple, has not easy answer. This is a complex topic that is not well understood by many. First sampling plan doesnt’ have a confidence interval. Confidence intervals are calculated after the sampling and inspection or test is complete. We need the number of defects found and the sample size adn the confidence level to calculate the interval.

Are you asking about the confidence level? For AQL plans taken from a published table, this is usually 95%. Btu we must remember that this is means (in your example) that 95% of the time when a defect rate of 1% is present, you will accept the lot.
 
Thread starter Similar threads Forum Replies Date
ScottK Statistical basis for 30 pieces for FAI 21 CFR Part 820 - US FDA Quality System Regulations (QSR) 7
Scott Catron Statistical basis for square-root sampling Inspection, Prints (Drawings), Testing, Sampling and Related Topics 11
N Design Verification & Process Validation - Statistical sample sizes Design and Development of Products and Processes 2
John Predmore Interactive visualization through graphical simulation of statistical concepts Statistical Analysis Tools, Techniques and SPC 3
Bev D Profound Statistical Concepts Misc. Quality Assurance and Business Systems Related Topics 63
A Statistical Analysis - Check if these organisms at different concentrations affect the growth of wheat seedlings Using Minitab Software 4
H Statistical Techniques Procedure - What should be included Document Control Systems, Procedures, Forms and Templates 4
O Statistical justification of sampling size in V&V tests ISO 13485:2016 - Medical Device Quality Management Systems 5
optomist1 It’s time to talk about ditching statistical significance Statistical Analysis Tools, Techniques and SPC 6
Marc Steve Prevette's Statistical Process Control (SPC) "Library" Statistical Analysis Tools, Techniques and SPC 0
John Predmore A Balanced view of statistical tests Statistical Analysis Tools, Techniques and SPC 3
S SPC (Statistical Process Control) for Unilateral Tolerance - Questions Statistical Analysis Tools, Techniques and SPC 6
S IATF 16949 9.1.1.3 Application of statistical concepts - Our technicians are quizzed for statistical knowledge IATF 16949 - Automotive Quality Systems Standard 3
K Please help identify appropriate statistical treatment Statistical Analysis Tools, Techniques and SPC 13
B IATF 16949 clause 7.1.5.1.1 - Statistical studies shall be conducted IATF 16949 - Automotive Quality Systems Standard 3
A Statistical Process Control and Inspection in Footwear Production Statistical Analysis Tools, Techniques and SPC 0
M IATF 16949 Cl. 7.1.5.1.1 - Statistical studies shall be conducted IATF 16949 - Automotive Quality Systems Standard 3
Steve Prevette Statistical Process Control Library Statistical Analysis Tools, Techniques and SPC 17
Marc Happy Birthday Statistical Steven - 2015 Covegratulations 10
L When are Statistical techniques not applicable? Service Industry Specific Topics 16
M FDA 21 CFR 820.250 - Does "valid statistical" always mean math? 21 CFR Part 820 - US FDA Quality System Regulations (QSR) 6
R Common Statistical Errors Using Minitab Software 1
Y Statistical Analysis of Road Traffic Data Statistical Analysis Tools, Techniques and SPC 11
B Class II Medical Device Manufacturer - SOP for 820.250 Statistical 21 CFR Part 820 - US FDA Quality System Regulations (QSR) 3
E Correct Statistical Test comparing 2 Groups Statistical Analysis Tools, Techniques and SPC 14
A Statistical Software Calibration using Ford's "Sample Calibration File" Statistical Analysis Tools, Techniques and SPC 8
J Defining Martial Arts and Gymnastics Statistical Techniques Statistical Analysis Tools, Techniques and SPC 4
J Capability Analysis - Unusual Statistical Distribution of my Proccess Capability, Accuracy and Stability - Processes, Machines, etc. 5
M PhD Thesis Data Statistical Analysis Methods Statistical Analysis Tools, Techniques and SPC 2
J Statistical Significance and SPC Control Chart Reports Statistical Analysis Tools, Techniques and SPC 9
N Statistical Quality Improvement Action for Small Batch Production Statistical Analysis Tools, Techniques and SPC 17
V Validation of macro - scripts - programs used in statistical software (Minitab-SAS... Qualification and Validation (including 21 CFR Part 11) 5
Moncia Statistical Process Control Crash Course - Question Quality Manager and Management Related Issues 10
H Statistical Models for Predictive Management of Software Processes Software Quality Assurance 2
A Statistical Correlation between ordered SKUs Statistical Analysis Tools, Techniques and SPC 8
S Minitab and Crystal Ball Statistical Analysis Software Using Minitab Software 13
M Determining if two different X's have any Statistical Significance on the Y's Statistical Analysis Tools, Techniques and SPC 4
I Statistical Stability for the PQ of Analytical Equipment Qualification and Validation (including 21 CFR Part 11) 1
F Statistical Comparison of Product: High Average vs. Low Range Capability, Accuracy and Stability - Processes, Machines, etc. 13
E Using ANOVA during the PQ Validation Run to evaluate Statistical Differences Statistical Analysis Tools, Techniques and SPC 4
W Gage R&R for gage pins used to inspect a hole ID called a Statistical Tolerance Gage R&R (GR&R) and MSA (Measurement Systems Analysis) 3
B AS 9100C sec 8.2.4 - " Recognized Statistical Principles" meaning AS9100, IAQG 9100, Nadcap and related Aerospace Standards and Requirements 7
R What is PSW - Statistical Process Package + Level 5 APQP and PPAP 7
O Is SPC (Statistical Process Control) always required? Statistical Analysis Tools, Techniques and SPC 4
V Any experience/feedback on statistical software tools...minitab -design expert -JMP Using Minitab Software 4
M SPC (Statistical Process Control) Book Recommendations wanted Book, Video, Blog and Web Site Reviews and Recommendations 1
I How to use Statistical Process Control (SPC)? Statistical Analysis Tools, Techniques and SPC 8
M TS 16949 8.1.1 Identification of Statistical Tools - Requirement Scope? IATF 16949 - Automotive Quality Systems Standard 13
D Appropriate Statistical Methods to set up an Alert/Warning Limit Quality Assurance and Compliance Software Tools and Solutions 15
J Applicable Statistical Analysis Method for this Data Six Sigma 17
Similar threads


















































Top Bottom