SBS - The best value in QMS software

Can someone clarify "Resolution", "Discrimination" and "ndc"?

C

Clouds - 2007

#1
Hi,
Q1:
According to MSA(3.0), p.43, discrimination and resolution can be said the same. It's all about the ratio of minimul scale of instrument over the range to be measured. The range is also refered to the tolerance of product, sometimes process variation. (1:10 is a suggested rule).
So, can I make such statement, that resolution/discrimination is a relative index (it depends on how big your production Tolerance is, or how big your process variation is.) it's not a absolute feature adhered with instrument? Yet the minimul scale is an adhered feature of instrument.

Q2:
ndc indicates how well the instrument can differentiate from process variation. Say 1, 5 or 20 categories, etc. It's again an relative index, depends on the tolerance/process variation. My question is, why in ndc, it's recommended to have >5 categories, yet the resolution is suggested to be at least 1:10?

Pls. help to clarify. Thank you very much.
clouds
 
Elsmar Forum Sponsor

harry

Super Moderator
#2
Welcome to the forum, Clouds.

It's Sunday night over in the US and therefore pretty quiet over here. Please be patient and I am sure you would get your answers by Monday (US time).

We have a number of regulars in the 'MSA' thread and I am sure they will respond to your question when they drop by.

Meanwhile do browse around for these issues had been discussed in great lengths previously.
 
Last edited:

Miner

Forum Moderator
Staff member
Admin
#4
Hi,
Q1:
According to MSA(3.0), p.43, discrimination and resolution can be said the same. It's all about the ratio of minimul scale of instrument over the range to be measured. The range is also refered to the tolerance of product, sometimes process variation. (1:10 is a suggested rule).
So, can I make such statement, that resolution/discrimination is a relative index (it depends on how big your production Tolerance is, or how big your process variation is.) it's not a absolute feature adhered with instrument? Yet the minimul scale is an adhered feature of instrument.
Not quite. Resolution and discrimination are indeed the same, but they are not a ratio. They are the smallest incremental measurement that a gage is capable of reading. For example, a digital micrometer that reads in 0.0005" increments has a resolution/discrimination of 0.0005". The 1:10 ratio that you mention is an old rule-of-thumb (guideline) used before MSA methods were developed. This guideline, though not perfect, did provide some allowance for measurement error. MSA studies have show that the 1:10 guideline is imperfect though, so it is really only useful for identifying potential gages.

Q2:
ndc indicates how well the instrument can differentiate from process variation. Say 1, 5 or 20 categories, etc. It's again an relative index, depends on the tolerance/process variation. My question is, why in ndc, it's recommended to have >5 categories, yet the resolution is suggested to be at least 1:10?

Pls. help to clarify. Thank you very much.
clouds
The two are not really related. The 1:10 guideline was based around the tolerance and ndc is based around the process capability. The guideline does not incorporate any measurement variation, while ndc does include measurement variation. There are so many differences that any comparison of the two is irrelevant.
 
C

Clouds - 2007

#5
Hi,
Thanks a lot for the knowledgable comments, and that's why I joined this forum.

rgds,
clouds,
 
Thread starter Similar threads Forum Replies Date
ScottK Can someone clarify the Trans Fat thing? i.e. What = Bad Coffee Break and Water Cooler Discussions 8
Crusader 4.2.4 Control of Records - Can someone please clarify "...and disposition of records" Records and Data - Quality, Legal and Other Evidence 7
A When someone refuses to follow a process.... Misc. Quality Assurance and Business Systems Related Topics 20
M Can someone share a scrubbed version of Clinical Evaluation Plan (CEP) EU Medical Device Regulations 8
I "On the job training" as a response to how someone was trained? ISO 9000, ISO 9001, and ISO 9004 Quality Management Systems Standards 75
I Root Cause Analysis when someone simply stops performing a task? ISO 9000, ISO 9001, and ISO 9004 Quality Management Systems Standards 16
T Misbranding (by someone we've contracted with) in a Publication 21 CFR Part 820 - US FDA Quality System Regulations (QSR) 15
Q QI Macro Histogram - Can someone define *sorted data*? Capability, Accuracy and Stability - Processes, Machines, etc. 7
J Can someone help me get the UCL AND LCL for this problem? Statistical Analysis Tools, Techniques and SPC 2
A Can someone provide an example of a Product Safety Policy? AS9100, IAQG, NADCAP and Aerospace related Standards and Requirements 1
L To share or not to share? Work distribution when someone goes on vacation Quality Manager and Management Related Issues 19
B What is the implication for someone who does not meet the 70% pass mark for QMS-Lead. Professional Certifications and Degrees 2
B Any future for someone working as Lead Quality right these days? ISO 9000, ISO 9001, and ISO 9004 Quality Management Systems Standards 6
C Can someone share example of FAI Inspection Plan ? Inspection, Prints (Drawings), Testing, Sampling and Related Topics 10
L Does someone has experience with a Supplier "Quality Watch" Supplier Quality Assurance and other Supplier Issues 3
R Full Time Internal Auditor - Where should I be looking for someone? Career and Occupation Discussions 15
P Can someone share their experience with KFDA Inspection ? Other Medical Device Regulations World-Wide 30
M Medical Device Regulation in Mongolia - Can someone help? Other Medical Device and Orthopedic Related Topics 3
R Someone can help me with the Volkswagen LiOn and BeON-QPN System? Customer and Company Specific Requirements 3
S Do Work Instructions need to be approved by someone other than the author? Document Control Systems, Procedures, Forms and Templates 14
E Can someone help me with ISO 11539:1999 for contact lens classification? Other US Medical Device Regulations 2
Jim Wynne Someone better "diffuse" me before I asplode Coffee Break and Water Cooler Discussions 7
B Does someone use APQP for non automotive industrie? IATF 16949 - Automotive Quality Systems Standard 2
D En 62366:2006 - Can someone explain what EN 62366:2006 covers? Other ISO and International Standards and European Regulations 3
G I hope someone can give me a hand.. Various Other Specifications, Standards, and related Requirements 4
1 Career Advice - What someone with my qualifications can shoot for Career and Occupation Discussions 7
S Seek advice from someone that passed through NADCAP AC7102 and AC7101/3 Various Other Specifications, Standards, and related Requirements 6
M Total Variation Formula - Can someone provide a source for this formula Gage R&R (GR&R) and MSA (Measurement Systems Analysis) 11
Q COQ (Cost of Quality) - Would someone review this doc and offer feedback? Benchmarking 10
K Internal Audit Guidelines for someone new Internal Auditing 12
Q Can someone share an Excel spreadsheet to measure Cpk or Cp values. Excel .xls Spreadsheet Templates and Tools 15
P Device marketed by someone else & different name...is a 510(k) required? 21 CFR Part 820 - US FDA Quality System Regulations (QSR) 18
J Can I get someone to help critique this manual? Quality Management System (QMS) Manuals 19
S Could someone tell me what are the results of a Gage R&R & how to interpret it? Gage R&R (GR&R) and MSA (Measurement Systems Analysis) 7
F Can someone to help to compare APQP and DMAIC? Six Sigma 10
C SPC presentation - How to convince someone to use SPC - Grind diameters Statistical Analysis Tools, Techniques and SPC 6
D Can Someone help me to understand....... Imported Legacy Blogs 3
Q REACH - Is it not the same as RoHS /IMDS? Can someone explain? RoHS, REACH, ELV, IMDS and Restricted Substances 1
J Sine Plate Charts - Someone lost the angle chart - Where can I get one? General Measurement Device and Calibration Topics 4
D Can someone take a look at my QM (Quality Manual)? Quality Management System (QMS) Manuals 7
A Internal Auditor - What is required to have someone qualified as an internal auditor? Other Medical Device and Orthopedic Related Topics 35
M Inspector Qualifications - Qualifying someone to be an inspector Inspection, Prints (Drawings), Testing, Sampling and Related Topics 12
GStough Looking for someone with experience in MDD, PPE, CMDR/CMDCAS regs General Auditing Discussions 1
H What I am trying to find is someone that remembers Memphis in the nineties Coffee Break and Water Cooler Discussions 10
ScottK Can someone explain the marketing behind this ad? Coffee Break and Water Cooler Discussions 21
M Escalation methods - Having to go over someone's head to address an issue Nonconformance and Corrective Action 6
E Synchronicity - Has someone lived an Event of Synchronicity? Coffee Break and Water Cooler Discussions 4
S DMR Index - Can someone share their Device Master Record Index structure or format? ISO 13485:2016 - Medical Device Quality Management Systems 15
M Internal Auditing Independence Rule - Can someone provide a good interpretation Internal Auditing 20
samer How can someone create his own acceptance criteria ? ISO 9000, ISO 9001, and ISO 9004 Quality Management Systems Standards 8

Similar threads

Top Bottom