a) to outline the general principles to be understood when assessing accuracy (trueness and precision) of measurement methods and results, and in applications, and to establish practical estimations of the various measures by experiment (GB/T 6379.1);
b) to provide a basic method for estimating the two extreme measures of the precision of measurement methods by experiment (GB/T 6379.2);
c) to provide a procedure for obtaining intermediate measures of precision, giving the circumstances in which they apply and methods for estimating them (ISO 5725-3);
d) to provide basic methods for the determination of the trueness of a measurement method (ISO 5725-4);
e) to provide some alternatives to the basic methods, given in GB/T 6379.2 and ISO 5725-4, for determining the precision and trueness of measurement methods for se under certain circumstances (ISO 5725-5);
f) to present some practical applications of these measures of trueness and precision.
1.2 This Part of GB/T 6379 is concerned exclusively with measurement methods which yield measurements on a continuous scale and give a single value as the test result, although this single value may be the outcome of a calculation from a set of observations.
This Part of GB/T 6379 defines values which describe, in quantitative terms, the ability of a measurement method to give a correct result (trueness) or to replicate a given result (precision). Thus there is an implication that exactly the same thing is being measured, in exactly the same way, and that the measurement process is under control.
This Part of GB/T 6379 may be applied to a very wide range of materials, including liquids, powders and solid objects, manufactured or naturally occurring, provided that due consideration is given to any heterogeneity of the material.
Foreword II Introduction III 1 Scope 2 Normative References 3 Definitions 4 Practical Implications of the Definitions for Accuracy Experiments 4.1 Standard measurement method 4.2 Accuracy experiment 4.3 Identical test items 4.4 Short intervals of time 4.5 Participating laboratories 4.6 Observation conditions 5 Statistical Model 5.1 Basic model 5.2 Relationship between the basic model and the precision 5.3 Alternative models 6 Experimental Design Considerations When Estimating Accuracy 6.1 Planning of an accuracy experiment 6.2 Standard measurement method 6.3 Selection of laboratories for the accuracy experiment 6.4 Selection of materials to be used for an accuracy experiment 7 Utilization of Accuracy Data 7.1 Publication of trueness and precision values 7.2 Practical applications of trueness and precision values Appendix A (Normative) Symbols and Abbreviations Used in GB/T 6379 Appendix B (Normative) Charts of Uncertainties for Precision Measures Appendix C (Informative) Bibliography
1.1 The purpose of GB/T 6379 is as follows:
a) to outline the general principles to be understood when assessing accuracy (trueness and precision) of measurement methods and results, and in applications, and to establish practical estimations of the various measures by experiment (GB/T 6379.1);
b) to provide a basic method for estimating the two extreme measures of the precision of measurement methods by experiment (GB/T 6379.2);
c) to provide a procedure for obtaining intermediate measures of precision, giving the circumstances in which they apply and methods for estimating them (ISO 5725-3);
d) to provide basic methods for the determination of the trueness of a measurement method (ISO 5725-4);
e) to provide some alternatives to the basic methods, given in GB/T 6379.2 and ISO 5725-4, for determining the precision and trueness of measurement methods for se under certain circumstances (ISO 5725-5);
f) to present some practical applications of these measures of trueness and precision.
1.2 This Part of GB/T 6379 is concerned exclusively with measurement methods which yield measurements on a continuous scale and give a single value as the test result, although this single value may be the outcome of a calculation from a set of observations.
This Part of GB/T 6379 defines values which describe, in quantitative terms, the ability of a measurement method to give a correct result (trueness) or to replicate a given result (precision). Thus there is an implication that exactly the same thing is being measured, in exactly the same way, and that the measurement process is under control.
This Part of GB/T 6379 may be applied to a very wide range of materials, including liquids, powders and solid objects, manufactured or naturally occurring, provided that due consideration is given to any heterogeneity of the material.
Contents of GB/T 6379.1-2004
Foreword II
Introduction III
1 Scope
2 Normative References
3 Definitions
4 Practical Implications of the Definitions for Accuracy Experiments
4.1 Standard measurement method
4.2 Accuracy experiment
4.3 Identical test items
4.4 Short intervals of time
4.5 Participating laboratories
4.6 Observation conditions
5 Statistical Model
5.1 Basic model
5.2 Relationship between the basic model and the precision
5.3 Alternative models
6 Experimental Design Considerations When Estimating Accuracy
6.1 Planning of an accuracy experiment
6.2 Standard measurement method
6.3 Selection of laboratories for the accuracy experiment
6.4 Selection of materials to be used for an accuracy experiment
7 Utilization of Accuracy Data
7.1 Publication of trueness and precision values
7.2 Practical applications of trueness and precision values
Appendix A (Normative) Symbols and Abbreviations Used in GB/T 6379
Appendix B (Normative) Charts of Uncertainties for Precision Measures
Appendix C (Informative) Bibliography
