FPY (First Pass Yeild) Calculations for Sampling

R

RickRay

#1
Hello,

I have a question on what would be the proper way to calculate FPY for an end item audit step?

Example: 200 units are produced in a run. 5 samples are taken. 1 sample is found to be nonconforming. Would you say your FPY rate is .995 or .8?

Thanks for you help and opinions.

Rick
 
Elsmar Forum Sponsor

Jim Wynne

Staff member
Admin
#6
Re: FPY Calculations for Sampling

Hello,

I have a question on what would be the proper way to calculate FPY for an end item audit step?

Example: 200 units are produced in a run. 5 samples are taken. 1 sample is found to be nonconforming. Would you say your FPY rate is .995 or .8?

Thanks for you help and opinions.

Rick
Neither would be correct; your example demonstrates that there is at least one defective in the lot of 200, but there might be more. Until you know how many there were, you can't calculate FPY and have it mean anything.
 
R

RickRay

#7
Re: FPY Calculations for Sampling

Yes FPY = First Pass Yield

Neither would be correct; your example demonstrates that there is at least one defective in the lot of 200, but there might be more. Until you know how many there were, you can't calculate FPY and have it mean anything.
Ok I would see the logic in that. So you would take another sample, let's say 5 more and if there were no further defects found?

Rick
 

Jim Wynne

Staff member
Admin
#8
Re: FPY Calculations for Sampling

Ok I would see the logic in that. So you would take another sample, let's say 5 more and if there were no further defects found?

Rick
If you want to know what the actual FPY is, you need to know how many defectives there are. In your example you have evidence that 20% (or more) of the lot could be bad. On the other hand, except for the defective found in the first five-piece sample, there might be no defects in the lot. Taking another five-piece sample isn't going to help much.
 

Tim Folkerts

Super Moderator
#9
Re: FPY Calculations for Sampling

I would say:

  • a lot with 1.3% defective will yield a sample with one in five bad 5% of the time (if you happen to select a bad item more often than average)
  • a lot with 53% defective will yield a sample with one in five bad 5% of the time(if you happen to select a bad item less often than average)
Therefore, the lot has FPY of 20% +23%/-18.7% with a 95% confidence level.


Tim F
 
R

RickRay

#10
Re: FPY Calculations for Sampling

If you want to know what the actual FPY is, you need to know how many defectives there are. In your example you have evidence that 20% (or more) of the lot could be bad. On the other hand, except for the defective found in the first five-piece sample, there might be no defects in the lot. Taking another five-piece sample isn't going to help much.
Ok so in other words trying to calculate FPY for this is probably not the way to go?
 
Thread starter Similar threads Forum Replies Date
B How to begin tracking FPY (First Pass Yield) and "Downtime" tracking Manufacturing and Related Processes 3
B Calculation of First Pass Yield (FPY) Six Sigma 9
S How to Calculate Overall FPY (First Pass Yield) Quality Tools, Improvement and Analysis 2
R Formula for calculating Money Value equivalent to 1% FPY (First Pass Yield) Six Sigma 5
P FPY (First Pass Yield) calculation acceptable? Quality Tools, Improvement and Analysis 2
L Is there any relationship between Cpk & Right First Time? First Pass Yield (FPY)? Capability, Accuracy and Stability - Processes, Machines, etc. 4
J Need Help with FPY Data in Assembly Process Manufacturing and Related Processes 7
P Is throughput yield the same as FPY or FTY? Rolled Throughput Yield Manufacturing and Related Processes 3
B Lowest cost way to pass Lead Auditor exam ISO 9000, ISO 9001, and ISO 9004 Quality Management Systems Standards 2
S Is using ANSI/ASQ Z1.4-2008 the correct sampling plan to determine Pass/Fail of Apparel measurements? AQL - Acceptable Quality Level 4
Crimpshrine13 IATF 16949 and ISO 9001 Remote Support - Pass Through Inventory IATF 16949 - Automotive Quality Systems Standard 20
A IATF certification for pass through supplier IATF 16949 - Automotive Quality Systems Standard 1
S How can a R&D center pass IATF 16949 certification? IATF 16949 - Automotive Quality Systems Standard 9
J AMS 2750 E Clause3.5.17.13 TUS Pass/Fail Requirements AS9100, IAQG, NADCAP and Aerospace related Standards and Requirements 2
Z Inspection Form With Pass/Fail Formula Excel .xls Spreadsheet Templates and Tools 11
B Best place is to purchase IEC 60417 labels that will pass markings test IEC 60601 - Medical Electrical Equipment Safety Standards Series 1
D Supplier Scorecard, Assessment of Pass Through Items From Sub Tier Suppliers Supplier Quality Assurance and other Supplier Issues 4
K UL 6601 - Would an off-the-shelf Android tablet, powered by USB, pass UL 6601? Other Medical Device Related Standards 3
Q Can a fail still be a pass? (Criteria Level B for 61000-4-6 Conducted Immunity) IEC 60601 - Medical Electrical Equipment Safety Standards Series 3
M What CQA Preparation Material helped you to pass the exam? Career and Occupation Discussions 6
I Device Can't Pass IEC 60601-2 ESD Requirements IEC 60601 - Medical Electrical Equipment Safety Standards Series 5
B What is the implication for someone who does not meet the 70% pass mark for QMS-Lead. Professional Certifications and Degrees 2
T First Pass Yield - Welding Process Improvement Manufacturing and Related Processes 3
C Difference between "Pass/Fail Testing" "Test To Failure" "Degradation Test" FMEA and Control Plans 1
Z Pass-Though Characteristics in PFMEA (Process FMEA) FMEA and Control Plans 2
S ISO 9001:2008 Sec 7.6 - Can we just log measurement devices as 'Pass/Fail'? ISO 9000, ISO 9001, and ISO 9004 Quality Management Systems Standards 118
S Verify Software System Testing: Verify that results meet the Pass/Fail Criteria IEC 62304 - Medical Device Software Life Cycle Processes 1
J Reliability Prove-out, Pass-Fail Testing Reliability Analysis - Predictions, Testing and Standards 2
I Supplier Using Reference Part for PASS/FAIL Inspection Supplier Quality Assurance and other Supplier Issues 8
G How much time must pass after the first Certification Audit for us to appear in OASIS AS9100, IAQG, NADCAP and Aerospace related Standards and Requirements 8
L Definition Throughput Yield (TPY) or First Pass Yield Calculation - Help Needed Definitions, Acronyms, Abbreviations and Interpretations Listed Alphabetically 3
N VDA 6.x - Requirements Pass Down to Suppliers ....Obliged?? VDA Standards - Germany's Automotive Standards 5
Hami812 Gage R&R on Automated Tool that supports Pass/Fail and some Parametric Testing Gage R&R (GR&R) and MSA (Measurement Systems Analysis) 3
J Contractor Pass required for Contract Cleaners? ISO 9000, ISO 9001, and ISO 9004 Quality Management Systems Standards 5
Hami812 Gage R&R Process Method - Pass/Fail Criteria Offered to Operators vs. Parametric Data Gage R&R (GR&R) and MSA (Measurement Systems Analysis) 5
G Hoffman Scratch Hardness Test - General Parameters for Pass/Fail (Paint Coatings) Inspection, Prints (Drawings), Testing, Sampling and Related Topics 1
R First Pass Yield - Am I doing correct the First Pass Yield Metric Quality Tools, Improvement and Analysis 2
M Limited Calibrations - An instrument that will not pass a full calibration, OOT General Measurement Device and Calibration Topics 8
F First Pass Yield Helped Requested Lean in Manufacturing and Service Industries 1
R Should the fault tests pass if temperature goes high in short time? IEC 60601 - Medical Electrical Equipment Safety Standards Series 15
K False Pass/Fail Information from GR&R (Gage R&R) Minitab Using Minitab Software 6
I Service Supplier Rating where Objective Pass/Fail Data is not Available Service Industry Specific Topics 7
R First Pass Yield Base Line Measurement Lean in Manufacturing and Service Industries 2
R ASQ CQE Practice Exam - Do I need to score very well to pass? Professional Certifications and Degrees 17
M Developing a CPI for First Pass Yield Final Inspection - Need help Quality Tools, Improvement and Analysis 7
R Pass Thru Gage for Straightness for a Floor Inspection Inspection, Prints (Drawings), Testing, Sampling and Related Topics 3
Q Is the up-dated ISO 9004:2009 needed to pass audit? ISO 9000, ISO 9001, and ISO 9004 Quality Management Systems Standards 22
QMMike Repercussions of letting your ISO/TS16949 RR date pass.... IATF 16949 - Automotive Quality Systems Standard 3
K Pass Thru Calibration Certificates? Out-Sourcing Calibration to 3rd Party General Measurement Device and Calibration Topics 6
D Cytotoxicity testing to ISO 10993-5 results - Is 1/ mild a pass or fail? Other Medical Device Related Standards 7

Similar threads

Top Bottom