marginTree.confusion {marginTree} | R Documentation |
A function giving a table of true versus predicted values, from a margin tree
marginTree.confusion(train.obj, threshold, extra=TRUE)
train.obj |
The result of a call to marginTree.train or marginTree.cv |
threshold |
The desired threshold value |
extra |
Should the classwise and overall error rates be returned? Default TRUE |
marginTree.confusion
Gives a cross-tabulation of true versus
predicted classes for the train.obj returned by marginTree or marginTree.cv,
at the specified threshold.
Robert Tibshirani and Trevor Hastie
#generate some data with 5 classes and 100 features set.seed(543) x=matrix(rnorm(40*1000),nrow=40) y=sort(rep(1:5,8)) x[y==2 | y==3, 1:50]=x[y==2|y==3, 1:50]+1 x[y==3,51:100]=x[y==3,51:100]+1 x[y==4|y==5,1:50]=x[y==4|y==5,1:50]-1 x[y==5, 51:100]=x[y==5,51:100]+1 #train the classifier train.obj<- marginTree(x,y) # print out confusion matrix marginTree.confusion(train.obj, threshold=.5) # do cross-validation and print out CV confusion matrix cv.obj<-marginTree.cv(x,y,train.obj) marginTree.confusion(cv.obj, threshold=.5)