How to apply the created model using PLSregress on test data?

Hi, I am using PLSRegress for 40 spectra with 150 features vs. some chemical data associated with each spectra. I can get the R-square for the regression but I am not able to get the model that is created using my training data. I want to apply the model to my test data to predict the chemical content. Anyone can help me about applying the model on my test data? This is the code I am using for training part: [Xloadings,Yloadings,Xscores,Yscores,betaPLS] = plsregress(X_Train,Y_Train,17,'CV',10);

[n,m] = size(X_Train);

yfitPLS = [ones(n,1) X_Train]*betaPLS;

plot(Y_Train,yfitPLS,'bo');

xlabel('Mg (Ground reference)');

ylabel('Mg (Prediction)');

TSS = sum((Y_Train-mean(Y_Train)).^2);

RSS_PLS = sum((Y_Train-yfitPLS).^2);

rsquaredPLS = 1 - RSS_PLS/TSS

Now I need to apply the created model on my test data which I couldn't figure out how!

Thanks

Answer 1

[Ali Farmanesh]

Hello, I think this script maybe can help you.

X=X_test; yval=Y_test; beta=betaPLS (you find this in your model) yvalfit = [ones(size(X,1),1) X]*beta;

TSSVal = sum((yval-mean(yval)).^2); RSSVal = sum((yval-yvalfit).^2); RsquaredVal = 1 - RSSVal/TSSVal