D2 vs d2* Explanation in My Terms

E

eturkan

#1
[FONT=&quot]I am a Math lover, recent Purdue MSME graduate and Gage R&R and statistics and Math is what I love since I started my career in QE. I had to spend less time to understand Navier-Stokes equation/tensor notations. I prepared an improvement opportunity list for MSA 4?th Ed and will send it to AIAG soon.[/FONT]
[FONT=&quot]
I'd like to thank everyone on the forum because the information I gain on the forum has been VERY helpful.[/FONT]
[FONT=&quot]As many other users I got confused between d2 and d2* because of misleading statements on MSA'th edition and the change in their methods (constants, d2 usage with small group sizes etc) with the earlier editions.

This is my first post (I believe) and I wanted to explain d2 vs d2* in my perception.[/FONT]
[FONT=&quot]In GRR, We calculate all R_bar in one or another way to determine the variation and, [/FONT]
[FONT=&quot]m= Length of the Range equation that is used [/FONT]
[FONT=&quot]R=(Max x(1),?.x(m))- (Min x(1),?.x(m)))[/FONT]
[FONT=&quot]g=How many unique range calculations do we have for the final R_bar value[/FONT]
[FONT=&quot]g= In R_bar= average (R(1)+...+R(g)) [/FONT]
[FONT=&quot] In a O (3 Operator) x T( 3 trials) x P (10 parts ) Gage R&R study (Prepare your own excel GRR Sheet for a better understanding. It takes 2 hours for a beginner but then you may have a solid understanding)[/FONT]
[FONT=&quot]Repeatability is calculated by first with a range operation for each individual reading set (Trial 1 thru Trial 3 so our Range equation length is 3[/FONT]
[FONT=&quot]Reproducibility is based on the average reading (of all parts and trials) of each operator. Our range equation is [/FONT]
[FONT=&quot]R=Max [ X_BAR_ (OP1) ,X_BAR_ (OP2) , X_BAR_ (OP2) ]- MIN [ X_BAR_ (OP1) ,X_BAR_ (OP2) , X_BAR_ (OP2) ][/FONT]
[FONT=&quot]So m=3 since the length of R is 3 in this example. [/FONT]
[FONT=&quot]g=1 since we only have ?1? unique R equation. [/FONT]
[FONT=&quot](There is a further deduction step due to contamination coming from repeatability but that is not the subject of this topic)[/FONT]

[FONT=&quot]Part to Part variation is calculated by comparing the average of all readings for each individual part [/FONT]
[FONT=&quot]R=Max [ X_BAR_ (PART1) ,X_BAR_ (PART2) ,?, X_BAR_ (PART10) ]- [/FONT]
[FONT=&quot]MIN [ X_BAR_ (PART1) ,X_BAR_ (PART2) ,?, X_BAR_ (PART10 ][/FONT]
[FONT=&quot]So m=10 since the length of R is 10 in this example. [/FONT]
[FONT=&quot]g=1 since we only have ?1? unique R equation.
[/FONT]


[FONT=&quot]I hope it's been helpful.
[/FONT]
 
Elsmar Forum Sponsor

Miner

Forum Moderator
Staff member
Admin
#2
Welcome to the cove. I am a long time ago Purdue grad (1982 BSMET). Good first post, and we hope to see you return often.
 

Bev D

Heretical Statistician
Staff member
Super Moderator
#4
:topic:
Nice start!

But I must start with a welcome from a Hoosier! Don't know if you were born in Indiana but I must welcome a purdue grad.

And Miner, you never said you were a boilermaker!

I am not, having graduated from michigan tech...
 

Miner

Forum Moderator
Staff member
Admin
#5
Bev, I am also a native Hoosier from southeast of Indy. I didn't realize that you were also.
 

Bev D

Heretical Statistician
Staff member
Super Moderator
#6
Miner - I was born in Columbus IN and raised in Huntington. Hoosier through and through.
 

Miner

Forum Moderator
Staff member
Admin
#7
Born and grew up in Shelbyville. Worked in Marion, Wabash, Peru and Logansport (same company, different plants). This is scary.
 
Thread starter Similar threads Forum Replies Date
A Six Sigma in terms of Statistics - An Explanation and Discussion Six Sigma 114
M IATF 16949 SI # 10: Integrated self-calibration of measurement equipment- Needs for explanation IATF 16949 - Automotive Quality Systems Standard 2
N Explanation - Quality means doing it right when no one is looking ISO 9000, ISO 9001, and ISO 9004 Quality Management Systems Standards 5
M Explanation about IQ, OQ, PQ for non-English speaker Qualification and Validation (including 21 CFR Part 11) 3
P Use of "N/A" in a Document - Is an explanation a requirement? ISO 13485:2016 - Medical Device Quality Management Systems 13
O Gage Study training explanation for Gage Users Gage R&R (GR&R) and MSA (Measurement Systems Analysis) 3
C Minitab Binomial Process Capability Analysis Chart Explanation Using Minitab Software 1
A Brief Explanation - Control, Capable and Stable Process Capability, Accuracy and Stability - Processes, Machines, etc. 2
M AS9100 5.6.2(c) Review Input: Process Performance - Detailed explanation needed AS9100, IAQG, NADCAP and Aerospace related Standards and Requirements 6
C Simple explanation of Uncertainty in Calibration Measurement Uncertainty (MU) 2
A Explanation of AS/EN 9100 Clause 7.4.1 Special Process Sources AS9100, IAQG, NADCAP and Aerospace related Standards and Requirements 5
D AIAG FMEA 4? Ed. Explanation: Relationship between PFMEA and Special Characteristics FMEA and Control Plans 8
R Confidence Level Explanation - Can I use confidence level below 95%? Using Minitab Software 4
S SPC Presentation and Explanation Training Materials for Beginners Training - Internal, External, Online and Distance Learning 2
X FDA Approval Process - Simple Explanation requested US Food and Drug Administration (FDA) 4
M Plain English Explanation of when to use which Normality Tests Quality Tools, Improvement and Analysis 7
G Explanation of Rule of Thumb (10:1) - Tolerance Zone or Digits Number Gage R&R (GR&R) and MSA (Measurement Systems Analysis) 3
M DFMEA Detection Ranking in AIAG FMEA Manual 4th Ed. - Explanation wanted IATF 16949 - Automotive Quality Systems Standard 6
S Aspect vs. Impact and Hazard vs. Risk - Short/clear explanation & example Miscellaneous Environmental Standards and EMS Related Discussions 11
Ajit Basrur Explanation for Medical Device definition US Food and Drug Administration (FDA) 2
V Can Anyone Give a Simple Explanation on ndc (number of distinct categories)? Gage R&R (GR&R) and MSA (Measurement Systems Analysis) 1
P Seamless Manufacturing in Automotive Manufacturing - An Explanation wanted Lean in Manufacturing and Service Industries 1
N Measurement Uncertainty Explanation per ISO/IEC 17025:2005 clause 5.10.4.2 ISO 17025 related Discussions 3
L Explanation of the note attached to 7.1(a) in AS 9100 Rev.C AS9100, IAQG, NADCAP and Aerospace related Standards and Requirements 5
P Good Vigilance Practice (GVP) - Japan - English translation and explanation of Japan Medical Device Regulations 8
S COPQ (Cost of Poor Quality) Vs PONC (Price of Non Conformance) - Explanation wanted Quality Manager and Management Related Issues 5
S Definition Modifiers in GD&T - Concept, Explanation and Application Definitions, Acronyms, Abbreviations and Interpretations Listed Alphabetically 2
G Objectives of Internal Audit 8.2.2 (a) - Explanation needed in plain English!! Internal Auditing 29
Chennaiite Automobile Differential Mechanism Explanation Video - Amazing Book, Video, Blog and Web Site Reviews and Recommendations 4
C Gage R&R 10:1 Tolerance to Gage Discrimination Rule Explanation Gage R&R (GR&R) and MSA (Measurement Systems Analysis) 9
S +/-6 sigma (range 12) for 3.4 DPM - Explanation please Six Sigma 4
R Chain Sampling Plan explanation and help - Reducing sample sizes (compared to Z1.4) Inspection, Prints (Drawings), Testing, Sampling and Related Topics 3
W Procedure Clause ?Level? Numbering System explanation ISO 9000, ISO 9001, and ISO 9004 Quality Management Systems Standards 5
T Double Sampling Plan Explanation for * Inspection, Prints (Drawings), Testing, Sampling and Related Topics 5
C An Explanation of Salt Spray (Corrosion) Testing based on ASTM B117 Design and Development of Products and Processes 1
Q ISO 14001 - 4.5.2 Evaluation of Compliance and explanation of 'Other Requirements' ISO 14001:2015 Specific Discussions 2
A ILAC explanation - IEC60601-1 testing certified by an A2LA laboratory IEC 60601 - Medical Electrical Equipment Safety Standards Series 3
B Statistical Analysis SPC Trend explanation needed Statistical Analysis Tools, Techniques and SPC 4
Q CAR Explanation for English as A Second Language (ESL) Employees Nonconformance and Corrective Action 1
A Calibration Accuracy Ratio - An explanation of the 10:1 or 4:1 rule General Measurement Device and Calibration Topics 4
B Legal document explanation for supplier charging Misc. Quality Assurance and Business Systems Related Topics 6
A Simplified Explanation of the 8 Quality Management Systems Requirements ISO 9000, ISO 9001, and ISO 9004 Quality Management Systems Standards 6
M Explanation of Sequence and Interaction of Processes ISO 9000, ISO 9001, and ISO 9004 Quality Management Systems Standards 6
M Source code and explanation for computer simulation in camera calibration, HELP Calibration and Metrology Software and Hardware 2
Jim Wynne An Explanation and an Apology Coffee Break and Water Cooler Discussions 33
S Explanation of Concentricity and Eccentricity Inspection, Prints (Drawings), Testing, Sampling and Related Topics 19
E QS 9000 Global Explanation - Sourcing manufacturers of auto parts Book, Video, Blog and Web Site Reviews and Recommendations 13
C Lot Cycle Time Measurement - Statistical explanation why 95%tile Lean in Manufacturing and Service Industries 9
M Product Audit - Explanation and samples of the report - TS 16949 General Auditing Discussions 53
H COP (Customer Oriented Process), MOP and SOP Examples and Explanation IATF 16949 - Automotive Quality Systems Standard 21

Similar threads

Top Bottom