I'm still learning to use caret package through The caret Package by Max Kuhn and got stuck in 16.2 Partial Least Squares Discriminant Analysis section while trying to predict using the plsBayesFit model through predict(plsBayesFit, head(testing), type = "prob") as shown in the book as well.
The data used is data(Sonar) from mlbench package, with the data being split as:
inTrain <- createDataPartition(Sonar$Class, p = 2/3, list = FALSE)
sonarTrain <- Sonar[ inTrain, -ncol(Sonar)]
sonarTest <- Sonar[-inTrain, -ncol(Sonar)]
trainClass <- Sonar[ inTrain, "Class"]
testClass <- Sonar[-inTrain, "Class"]
and then preprocessed as follows:
centerScale <- preProcess(sonarTrain)
centerScale
training <- predict(centerScale, sonarTrain)
testing <- predict(centerScale, sonarTest)
after this the model is trained using plsBayesFit <- plsda(training, trainClass, ncomp = 20, probMethod = "Bayes"), followed by predicted using predict(plsBayesFit, head(testing), type = "prob").
When I'm trying to do this I get the following error:
Error in predict.NaiveBayes(object$probModel[[ncomp[i]]], as.data.frame(tmpPred[, : Not all variable names used in object found in newdata
I've checked both the training and testing sets to check for any missing variable but there isn't any. I've also tried to predict using the 2.7.1 version of pls package which was used to render the book at that time but that too is giving me same error. What's happening?
I've tried to replicate your problem using different models, as I have encountered this error as well, but I failed; and caret seems to behave differently now from when I used it.
In any case stumbled upon this Github-issues here, and it seems like that there is a specific problem with the klaR-package. So my guess is that this is simply a bug - and nothing that can be readily fixed here!