I made a tree classification model with the package 'rpart' and met some problems.
This is my code, coupled with errors and output.
#Using the rpart package generate a classification tree predicting certified from the other variables in the M1 data frame.
c.tree1 = rpart(factor(certified)~., method="class", data=M1)
'Error in plot.rpart(tree, uniform = TRUE, branch = 0.2, compress = TRUE, : fit is not a tree, just a root'
#Check the results from the classifcation tree using the printcp() command
printcp(c.tree1)
Classification tree:
rpart(formula = factor(certified) ~ ., data = M1, method = "class")
Variables actually used in tree construction:
character(0)
Root node error: 204/1000 = 0.204
n= 1000
CP nsplit rel error xerror xstd
1 0 0 1 0 0
#Plot your tree
post(c.tree1,file='',title='Tree1')
'Error in plot.rpart(tree, uniform = TRUE, branch = 0.2, compress = TRUE, : fit is not a tree, just a root'
Does anyone know why this has happened and how to solve this problem? Thanks very much.