Building NIR Calibration Models and Avoiding Common Chemometric Mistakes Knowing the theory behind PLS and PCR is different from knowing how to build a calibration that holds up. <p>Knowing the theory behind PLS and PCR is different from knowing how to build a calibration that holds up. This article covers the practical side: how NIR calibration models are actually built, the most common modeling mistakes practitioners make, and how to get more consistent performance from your NIR instrument.</p> <p>Building a reliable calibration isn't a one-step process. Here's the sequence that good calibration development follows:</p> <p>The most common trap I see when visiting plants is overfitting . This is when a model fits the training data too closely — including its noise — and then performs poorly on new samples. It's like memorizing exam answers instead of understanding the subject. The model looks great on paper but fails in production.</p> <h2>How NIR Calibration Models Are Built</h2> <h2>Common Mistakes in NIR Chemometric Modeling</h2> <p>External Resources: <a href="https://www.foragelab.com/media/accurate%20analysis%20nirs%20versus%20wet%20chemistry.pdf">https://www.foragelab.com/media/accurate%20analysis%20nirs%20versus%20wet%20chemistry.pdf</a> | <a href="https://www.iso.org/standard/12770.html">https://www.iso.org/standard/12770.html</a> | <a href="https://www.walshmedicalmedia.com/open-access/the-role-of-chemometrics-in-enhancing-the-accuracy-of-analytical-data-in-complex-mixtures-131404.html">https://www.walshmedicalmedia.com/open-access/the-role-of-chemometrics-in-enhancing-the-accuracy-of-analytical-data-in-complex-mixtures-131404.html</a></p> ← Back to NIR Spectroscopy Blog