The View from Eigenvector
EigenNews and EigenViews from Barry and the Eigenvector staff.
Re-orthogonalization of PLS Algorithms
Aug 23, 2010
Thanks to everybody that responded to the last post on Accuracy of PLS Algorithms. As I expected, it sparked some nice discussion on the chemometrics listserv (ICS-L)! As part of this discussion, I got a nice note from Klaas Faber reminding me of the short communication he wrote with Joan Ferré, “On the numerical stability […]
Accuracy of PLS Algorithms
Aug 13, 2010
In 2009 Martin Andersson published “A comparison of nine PLS1 algorithms” in Journal of Chemometrics[1]. This was a very nice piece of work and of particular interest to me as I have worked on PLS algorithms myself [2,3] and we include two algorithms (NIPALS and SIMPLS) in PLS_Toolbox and Solo. Andersson compared regression vectors calculated […]
Clustering in Images
Aug 6, 2010
It is probably an understatement to say that here are many methods for cluster analysis. However, most clustering methods don’t work well for large data sets. This is because they require computation of the matrix that defines the distance between all the samples. If you have n samples, then this matrix is n x n. […]