R trying to get caret / rfe to work

Question

I have a data set that I\'m trying to use rfe() from the caret package in R on.

x is the prices I\'m trying to predict.

y is the va

Answer 1

It should be factor and vector:

as.factor(noquote(as.vector(t(df[,14])))) 

In my case column 14 is a class in df.

Answer 2

y should be a numeric or factor vector. Here you have it as a data frame. Compare:

> rfe(data.frame(matrix(rnorm(100*3), ncol=3)), sample(2, 100, replace=T), sizes=1:3, rfeControl=rfeControl(functions=lmFuncs))

Recursive feature selection

Outer resampling method: Bootstrap (25 reps) 

Resampling performance over subset size:

 Variables   RMSE Rsquared  RMSESD RsquaredSD Selected
         1 0.5154  0.02120 0.02421    0.02752        *
         2 0.5162  0.02295 0.02722    0.03204         
         3 0.5162  0.02295 0.02722    0.03204         

The top 1 variables (out of 1):
   X3

vs.

> rfe(data.frame(matrix(rnorm(100*3), ncol=3)), data.frame(sample(2, 100, replace=T)), sizes=1:3, rfeControl=rfeControl(functions=lmFuncs))
Error in rfe.default(data.frame(matrix(rnorm(100 * 3), ncol = 3)), data.frame(sample(2,  : 
  there should be the same number of samples in x and y