# Purpose of calculating Ta, Tb & R Square in Linearity Study

P

#### Prasanna Venkatesh

Dear all,

Can you please explain what is the purpose of calculating Ta, Tb & R Square in linearity study & how to conclude the study by seeing the Graphical analysis chart. I could not able to understand this calculation. Please help me.

#### Miner

##### Forum Moderator
Staff member
ta = the test statistic for the null hypothesis that the slope = 0.
tb = the test statistic for the null hypothesis that the intercept = 0.
R^2 is the percentage of variation explained by the linearity.

Ideally, both ta and tb are not statistically different from zero, and R^2 is relatively low. If they are statistically significant, then there is a linearity issue with the gage.

Regarding the graphical analysis, the Bias = 0 line should fall within the 95% CI bands for the regression line. If it does not there is a linearity problem with the gage.

P Purpose of calculating Uncertainty value in calibration study Measurement Uncertainty (MU) 5
J Calculating Repeat Business for the purpose of quantifying a Quality Objective ISO 9000, ISO 9001, and ISO 9004 Quality Management Systems Standards 2
ISO 13485 for general purpose disinfectants? ISO 13485:2016 - Medical Device Quality Management Systems 9
Records required for ISO 9001 clause 7.1.5.1 - Fitness for purpose of the monitoring and measurement resources ISO 9000, ISO 9001, and ISO 9004 Quality Management Systems Standards 10
A purpose of a Stage 1 audit - Off site document review Registrars and Notified Bodies 3
Audit purpose - case study - What is the role of SQE in such case? General Auditing Discussions 3
A True purpose of doing EST (Electrical Safety Test) on medical device Other Medical Device Related Standards 3
Informational What is the purpose of Internal Audits? Internal Auditing 27
K QMS Improvement - Analyze the systemic weaknesses of the QMS for improvement purpose Quality Tools, Improvement and Analysis 6
Difference between intended purpose and intended use of the device EU Medical Device Regulations 9
J Purpose of Reference Section in SOPs Document Control Systems, Procedures, Forms and Templates 6
Can a literature alone be used for the purpose of Clinical Evaluation of a device? EU Medical Device Regulations 6
E IATF 16949 Cl. 7.1.5.1 - Documented information as evidence of fitness for purpose IATF 16949 - Automotive Quality Systems Standard 3
Auditing Fitness of Purpose for Monitoring and Measuring Equipment ISO 9000, ISO 9001, and ISO 9004 Quality Management Systems Standards 3
J Are dermal fillers & PDO sutures for aesthetic purpose under CE MDD? EU Medical Device Regulations 6
Electronic data Back-up procedure, for Medical device QMS and regulatory purpose. ISO 13485:2016 - Medical Device Quality Management Systems 4
Q IEC 60601 for Non-Medical Research Purpose Devices IEC 60601 - Medical Electrical Equipment Safety Standards Series 7
UV Absorption Test - What is it's purpose and what specifically is it looking for? Other Medical Device Related Standards 9
A ISO/IEC 20000 Toolkit For Academic Purpose IT (Information Technology) Service Management 6
L What is, and the purpose of, ISO STATS recording ISO 9000, ISO 9001, and ISO 9004 Quality Management Systems Standards 3
Hardcopy and Electronic Forms for same purpose vs. Naming and Numbering System Document Control Systems, Procedures, Forms and Templates 1
How to qualify (IQ, OQ, PQ) a multi-purpose equipment ? Imported Legacy Blogs 1
V The Purpose of Basic Dimensions on Prints APQP and PPAP 6
Q Beginner's Understanding - The Purpose and Applications of QMS/ISO Standards Philosophy, Gurus, Innovation and Evolution 12
J How to qualify (IQ, OQ, PQ) a multi-purpose equipment ? Qualification and Validation (including 21 CFR Part 11) 5
S Logo Marking for Marketing purpose - ISO 9001, ISO 14001 and OHSAS 18001 ISO 9000, ISO 9001, and ISO 9004 Quality Management Systems Standards 1
P What is the latest version of ISO 10021 used for Certification purpose? Other ISO and International Standards and European Regulations 3
N Export & Import of Unapproved Device in USA for Service Purpose Only 21 CFR Part 820 - US FDA Quality System Regulations (QSR) 1
C Purpose of the Quality Manual for an Organisation Quality Management System (QMS) Manuals 4
TS 16949 Clause 7.5.1.8 - Special-Purpose Tools or Measurement Equipment IATF 16949 - Automotive Quality Systems Standard 2
A FDA: Label Requirements for General Purpose Reagents IVD 21 CFR Part 820 - US FDA Quality System Regulations (QSR) 5
A What is the purpose of using AQL (Acceptable Quality Level) for Sampling? AQL - Acceptable Quality Level 3
S What is the purpose of ON HOLD Labels Food Safety - ISO 22000, HACCP (21 CFR 120) 5
Q How to write Statement of Purpose for a Law School Admission Career and Occupation Discussions 9
C FDA Approval Process for Device that can also be used for Veterinary Purpose 21 CFR Part 820 - US FDA Quality System Regulations (QSR) 6
R Can some one share JIS B7502/7507 or DIN862 with me for study purpose? General Measurement Device and Calibration Topics 2
What is the Purpose of or Requirement for having a Gage Glossary? IATF 16949 - Automotive Quality Systems Standard 2
P What is the purpose and use of Chart Stickers Labels? 21 CFR Part 820 - US FDA Quality System Regulations (QSR) 1
A Auditor suggested company find a higher purpose for Internal Audits ISO 9000, ISO 9001, and ISO 9004 Quality Management Systems Standards 10
C Purpose of using different Distributions to solve Reliability Problems? Reliability Analysis - Predictions, Testing and Standards 2
Z CMM Measuring Instruction - Example needed for translation purpose Document Control Systems, Procedures, Forms and Templates 17
L Please share some practical SPC exercises for training purpose Statistical Analysis Tools, Techniques and SPC 4
Intended Use vs. Intended Purpose vs. Intended by the Manufacturer - Doubts ISO 13485:2016 - Medical Device Quality Management Systems 9
S What is the purpose of Critical to Quality tree (CTQ)? Six Sigma 2
Q Using Class 3 used Electronic Devices for Training purpose ISO 13485:2016 - Medical Device Quality Management Systems 1
R Copy of TS16949:1999 for reading purpose IATF 16949 - Automotive Quality Systems Standard 7
R What is the purpose of Benchmarking? Benchmarking 5
K Process Tailoring - What is the purpose of process tailoring? Software Quality Assurance 12
U What is the purpose of a Software Test Plan? Software Quality Assurance 7
P Six Sigma Case Studies and Exercise material for practice purpose. Six Sigma 12