Determination and use of straight-line calibration functions
Document Title [Hindi] :
सीधी-रेखा अंशांकन कार्यों का निर्धारण और उपयोग
Document Type :
New
Language :
English
Priority :
3
ICS Code :
03.120.30
Date of Project Approval :
05-03-2024
Standards to be Superseded :
Classification Details
Group :
Management systems/services and corporate social responsibilities
Sub Group :
Statistical quality control
Sub Sub Group :
Statistical Quality Control Methods
Aspects :
Others
Risk :
None
Certification :
None
Short Commom Man's Title :
ITCHS Code :
Ministry :
Sustainable development Goals :
Degree of Equivalence :
Identical under single numbering
Identical/Equivalent Standards :
ISO/TS 28037:2010
Organization Type:
ISO
Division Council Chairperson Approval Details
Sl.No.
Synosis Points
1
This Technical Specification is concerned with linear, that is, straight-line, calibration functions that describe the relationship between two variables X and Y, namely, functions of the form Y = A + BX. Although many of the principles apply to more general types of calibration function, the approaches described exploit the simple form of the straight-line calibration function wherever possible.
2
Values of the parameters A and B, are determined on the basis of measured data points (xi; yi), i = 1,…,m. Various cases are considered relating to the nature of the uncertainties associated with these data. No assumption is made that the errors relating to the yi are homoscedastic (having equal variance), and similarly for the xi when the errors are not negligible.
3
Estimates of the parameters A and B are determined using least squares methods. The emphasis of this Technical Specification is on choosing the least squares method most appropriate for the type of measurement data, in particular methods that reflect the associated uncertainties. The most general type of covariance matrix associated with the measurement data is treated, but important special cases that lead to simpler calculations are described in detail.
4
For all cases considered, methods for validating the use of the straight-line calibration functions and for evaluating the uncertainties and covariance associated with the parameter estimates are given.
5
The Technical Specification also describes the use of the calibration function parameter estimates and their associated uncertainties and covariance to predict a value of X and its associated standard uncertainty given a measured value of Y and its associated standard uncertainty.
6
NOTE 1 The Technical Specification does not give a general treatment of outliers in measurement data, although the validation tests given can be used as a basis for identifying discrepant data.
7
NOTE 2 The Technical Specification describes a method to evaluate the uncertainties associated with the measurement data in the case that those uncertainties are known only up to a scale factor (Annex E).