## Column: Chemometrics in Spectroscopy

Jun 01, 2018
Spectroscopy
Calibration transfer involves several strategies and mathematical techniques for applying a single calibration database consisting of samples, reference data, and calibration equations to two or more instruments. In this installment, we review the chemometric and tactical strategies used for the calibration transfer process.
Feb 01, 2018
Spectroscopy
How can you detect the presence of an outlier when it is mixed with multiple other, similar, samples?
Oct 01, 2017
Spectroscopy
Calibration transfer involves multiple strategies and mathematical techniques for applying a single calibration database to two or more instruments. Here, we explain the methods to modify the spectra or regression vectors to correct differences between instruments.
Jun 01, 2017
Spectroscopy
Outliers are fundamentally a very fuzzy notion. Here, we try to clear up what outliers are and how they affect your data.
Feb 01, 2017
Spectroscopy
Bias and slope adjustments are the most bothersome issues associated with the routine use of multivariate models for quantitative analysis in spectroscopy. Here, we delve into the issues causing prediction error, bias, and slope changes.
Nov 01, 2016
Spectroscopy
We continue our discussion of statistics with an examination of the principle of least squares.
Jun 01, 2016
Spectroscopy
There is some confusion about the use of degrees of freedom (df) for various calibration and prediction situations. The problem lies in computing a standard deviation using different df values without a more rigorous explanation and then placing emphasis on the actual number derived for the standard error, rather than on the computed confidence intervals.
Feb 01, 2016
Spectroscopy
A detailed explanation of the principle of analysis of variance.
Oct 01, 2015
Spectroscopy
Modern statistics rests on three foundational principles. Here, we explain the first of these. But instead of getting involved in the nitty gritty of the equations, we approach this topic from the top down, concentrating on the core principles that apply to all major aspects of the use and application of statistical thought.
Jul 01, 2015
Spectroscopy
Why does this problem continue to plague researchers and users of chemometrics and spectroscopy?
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