Figmerit

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Revision as of 14:25, 3 September 2008 by imported>Jeremy (Importing text file)
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Purpose

Analytical figures of merit for multivariate calibration.

Synopsis

[nas,nnas,sens,sel] = figmerit(x,y,b);

Description

Calculates analytical figures of merit for PLS and PCR standard model structures. Inputs are the preprocessed (usually centered and scaled) spectral data x, the preprocessed analyte data y, and the regression vector, b. Note that for standard PLS and PCR structures b = model.reg.

The outputs are the matrix of net analyte signals nas for each row of x, the norm of the net analyte signal for each row nnas (this is corrected to include the sign of the prediction), the matrix of sensitivities for each sample sens, and the vector of selectivities for each sample sel (sel is always non-negative).

Note that the "noise-filtered" estimate present in previous versions is no longer used because an improved method for calculating the net analyte vector makes it redundant

Examples

Given the 7 LV PLS model:

modl = pls(x,y,7);
Rhat = modl.loads{1,1}\*modl.loads{2,1}';
[nas,nnas,sens,sel,nfnas] = figmerit(x,y,Rhat);

Given the 5 PC PCR model:

modl = pcr(auto(x),auto(y),5);
Rhat = modl.loads{1,1}\*modl.loads{2,1}';
[nas,nnas,sens,sel,nfnas] = figmerit(auto(x),auto(y),Rhat);

See Also

pcr, pls