randomForests predict problem
Well, thank you for your answer, but this is not doing the right thing,
that is predicting the Class value for the test set Soybean[test,]. It
gives instead prediction for data used for forest computation (ignoring all
data with NA's) ; 'data' argument is simply ignored as the right name for
this argument is 'newdata', which still gives the same error when named.
> length(sb.rf.pred)
[1] 445
> dim(Soybean[test,])
[1] 150 36
> dim(Soybean[-test,])
[1] 533 36
> sb.rf.pred <- predict(sb.rf, newdata=st)
Error in matrix(t1$countts, nr = nclass, nc = ntest) :
No data to replace in matrix(...)
At 13:13 02/04/03, you wrote:
Hello everybody, I'm testing the randomForest package in order to do some simulations and I get some trouble with the prediction of new values. The random forest computation is fine but each time I try to predict values with the newly created object, I get an error message. I thought I was because NA values in the dataframe, but I cleaned them and still got the same error. What am I doing wrong ?
> library(mlbench) > library(randomForest) > data(Soybean) > test <- sample(1:683, 150, replace=F) > sb.rf <- randomForest(Class~., data=Soybean[-test,]) > sb.rf.pred <- predict(sb.rf, Soybean[test,])
Error in matrix(t1$countts, nr = nclass, nc = ntest) :
No data to replace in matrix(...)
try R> test <- sample(1:683, 150, replace=FALSE) R> R> st <- Soybean[test,] R> R> sb.rf <- randomForest(Class~., data=Soybean, subset=-test) R> sb.rf.pred <- predict(sb.rf, data=st) R> R> sb.rf.pred[1:10] [1] diaporthe-stem-canker diaporthe-stem-canker diaporthe-stem-canker [4] diaporthe-stem-canker diaporthe-stem-canker diaporthe-stem-canker [7] diaporthe-stem-canker charcoal-rot charcoal-rot [10] charcoal-rot 19 Levels: 2-4-d-injury alternarialeaf-spot anthracnose ... rhizoctonia-root-rot Torsten