https://nirpyresearch.com Statistical learning and chemometrics in Python Sat, 12 Sep 2026 09:37:58 +0000 en-AU hourly 1 https://wordpress.org/?v=7.1.3 https://nirpyresearch.com/wp-content/uploads/2019/07/apple-icon-152x152-1-150x150.png https://nirpyresearch.com 32 32 https://nirpyresearch.com/robust-pca/ Sun, 17 Mar 2024 08:43:04 +0000 https://nirpyresearch.com/?p=3150 A implementation of robust PCA, useful when the data contains outliers.]]> https://nirpyresearch.com/multi-class-classification-nir-spectroscopy/ Sat, 08 Jul 2023 10:03:50 +0000 https://nirpyresearch.com/?p=2757 Multi-class classification aims and subdividing samples into one of multiple predefined categories. In this post we explore a basic classifier and discuss important metrics such as accuracy and AUC score. ]]> https://nirpyresearch.com/pca-correlation-circle/ Sat, 03 Sep 2022 09:23:48 +0000 https://nirpyresearch.com/?p=2771 The PCA correlation circle is a useful tool to visually display the correlation between spectral bands and principal components. The correlation can be quantified through the Euclidean distance and used to colour code spectral bands for further insight.]]> https://nirpyresearch.com/pca-kernel-pca-explained/ Wed, 10 Jun 2020 09:24:35 +0000 https://nirpyresearch.com/?p=2337 Gain a practical understanding of PCA and kernel PCA by learning to code the algorithms and test it on real spectroscopic data.]]> https://nirpyresearch.com/detecting-outliers-using-mahalanobis-distance-pca-python/ Sun, 20 Jan 2019 05:13:20 +0000 https://www.idtools.com.au/?p=1558 How do we make sure we are detecting only true outliers and not cherry-picking from the data? Here's a method based on the Mahalanobis distance with PCA.]]> https://nirpyresearch.com/classification-nir-spectra-principal-component-analysis-python/ Thu, 22 Mar 2018 19:41:00 +0000 http://www.idtools.com.au/?p=1025 An in-depth tutorial on how to run a classification of NIR spectra using Principal Component Analysis in Python. Step by step example with code.]]> https://nirpyresearch.com/nir-classification-macadamia-kernels/ Wed, 05 Jul 2017 21:18:22 +0000 http://www.idtools.com.au/?p=679 Can we use NIR analysis to grade macadamias? Check out our preliminary results of NIR classification of macadamia kernels using Principal Component Analysis.]]>