Blog Archives

Working with Shootout – 2012 in R (001)

October 29, 2012
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Working with Shootout – 2012 in R (001)

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...

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Looking to the PCA scores with GGobi

October 21, 2012
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Looking to the PCA scores with GGobi

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...

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PCA with "ChemoSpec" – 001

October 20, 2012
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PCA with "ChemoSpec" – 001

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...

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PLS2 with "R"

September 22, 2012
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PLS2 with "R"

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...

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Monitor: Using category labels

July 26, 2012
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Monitor: Using category labels

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...

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Hierarchical Cluster Analysis (ChemoSpec) – 03

July 25, 2012
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Hierarchical Cluster Analysis (ChemoSpec) – 03

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...

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Hierarchical Cluster Analysis (ChemoSpec) – 02

July 19, 2012
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Hierarchical Cluster Analysis (ChemoSpec) – 02

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...

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Monitor with R: Moisture in Sunflower Seeds Intact

July 18, 2012
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Monitor with R: Moisture in Sunflower Seeds Intact

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...

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Hierarchical Cluster Analysis (ChemoSpec) – 01

July 17, 2012
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Hierarchical Cluster Analysis (ChemoSpec) – 01

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 ...

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Olive vs. Sunflower oil Spectra – 002 (ChemoSpec)

July 1, 2012
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Olive vs. Sunflower oil Spectra – 002 (ChemoSpec)

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...

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