Active Standard: D6122 - 13
For multivariate calibration models such as those used on process IR analyzers, sample (matrix) specific biases can be a significant portion of the model error. These calibration models are typically developed on large numbers of samples covering a wide range of composition and process variation. Initial validation is done on only 20 samples which span a far smaller range of composition and process variation. As a result, the inherent sample (matrix) specific biases can lead to an apparent bias during initial validation. While the bias may be significant relative to the variation of these initial results, it may well be within the expected range of sample specific biases seen during the calibration. The D6708 based validation needs to be reexamined to take into account sample (matrix) specific biases inherent to these types models to provide better recommendations on interpretation of results and actions to take based on results.
Keywordscontrol chart; infrared analyzer; infrared spectrophotometers; IR spectroscopy; multivariate process; NIR spectroscopy; statistical quality assurance; validation;
Draft Under Development