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Histograms of all the sample sets together and individuallyRaw SpectraSpectra treated with MSC (Multiple Scatter correction)Spectra treated with SG filters

It is obvious (after seeing the spectra of the calibration set), that we have at least three clusters, and that this can be related with the concentration of the active ingredient in the tablets. If we see the scores in the PC1-PC2 score map we will se...

I have downloaded (from the IDRC) the ASCI files of the Shootout 2012 (see: Shootout 2012 files), so I can work with the data  to develop a model and predict a Validation Set.For that task I have a "Calibration Set", and a  "Test Se...

In this post I continue with the unsupervised exploration of oil spectra, which we have seen in previous post ( PCA with "ChemoSpec" - 001).In the manual "ChemoSpec:An R Package for Chemometric Analysis of Spectroscopic Data", (page 23) there is a brie...

In my last post about "ChemoSpec package" (Hierarchical Cluster Analysis (ChemoSpec) - 02), we saw the two cluster groups (one for olive oil, other for sunflower oil), and also another sub-clusters for the sunflower oil.Continue reading the manual "Che...

I´ve been working these days with PLS2 calibrations with a chemometric software called “Unscrambler” with a data set called “jam”. I said “can I develop PLS2 models with R?”.I look in the book “Introduction to Multivariate Statistical An...

I´ve been checking recently the performance of a calibration of compound feed with  a set of samples (15): 3 samples of hen feed, 3 of pig feed, 3 of chicken feed, 3 of ovine feed and 3 of cattle feed.The idea is to check if the calibration predi...

It is clear that we can discriminate between olive oil and sunflower oil, but let´s see the reason for the sub-clusters in the sunflower oil.Samples sflw6da, sflw7da, sflw8da, sflw9da, sflw10da are refined sunflower, so it is filtered and processed, t...

This is the second derivative spectra of the raw spectra we have sawn in the post: "Hierarchical Cluster Analysis (ChemoSpec) - 01". In that post we saw some clusters, but the distance between the clusters was not high, so it was clear that some m...

I had the opportunity today to check the performance of a calibration (moisture in intact sunflower seed in reflectance).This is always a exciting moment:  Does the performance of the calibration for the new validation set is as expected duri...

I have been in previous post using the ChemoSpec package for some oil data (olive and sunflower). My spectra has now a range from 1100nm to 2200nm and is raw (not treated mathematically) . I want to start using the ChemoSpec package to start using the ...

I add other data set of “sunflower oil” to import together with the olive oil into ChemoSpec R package. Before, as I showed in a video (Preparing spectra to import into ChemoSpec), every sample has been acquired with a NIR instrument (in transmitta...

In this video I show I to prepare a spectrum to import later into ChemoSpec:The software I use gives the option to export the spectrum as a TXT file.This file is open with Excel and saved as CSV, to import later with others into ChemoSpec.

I continue with the practicing with ChemSpec, and this time I import seven spectra of olive oil. This time I have been more careful and I have the frequency column as numeric form the CSV file. Once I have the spectra (with and offset):Take in account ...

I’ve been this week trying to import some spectra to ChemoSpec (R Package), at the beginning I had problems generating the “csv”  files, and the function getManyCsv did not recognize the files. I did not have properly configured the regional...

I add a new video “Should I adjust the slope”, where a new part of script is added to the monitor function.  I don´t recommend adjusting the slope, but there are circumstances where it is necessary:Suppose you have an equation, but not the ca...

New Monitor Video:Improving Monitor statistics with the "UECLs"

I have fixed the link to the video "Removing Y outliers from the validation set" and it´s time to see what could be the next step to the function. As we know the RMSEP is the sum of the explained (BIAS) and unexplained error (SEP). We get also the ...