plotting roc curve in R problem: x axis is in opposite direction

Question

I am coding with R and trying to plot roc curve after randomForest classification :

rf.roc<- roc(Y , Votes)
  file1=paste( "cv_average", Cancer,".AUC.RF" , ".pdf" , sep="" )
  pdf(file=file1  ,width = 5 , height = 5 )
  plotRF<-plot.roc(rf.roc,main=paste(Cancer , " vs. others",  " average of cv RF" , sep="")
               ,col=1,lwd=4, cex.lab=1.5 , cex.main=1.1 , cex.lab=1.1)
    text(x=0.7 , y=0.65 , label=paste("mean_accuracy=" , round(acc.RF , digits = 4) , sep="")  , cex=1 ,font=2)
    text(x=0.7 , y=0.8  ,label=paste("AUC= ",round( auc(rf.roc), digits = 4) , sep = "") , cex=1 , font=2 )
  print(plotRF)
  dev.off()

as you can see x axes is in opposite direction!

rf.roc
Data: Votes in 557 controls (Y 0) < 120 cases (Y 1).
Area under the curve: 0.9966

I would appreciate it if someone could help me fix this

Please share the data set or part of it in order to make reproducible your code. — Scipione Sarlo, May 08 '21 at 10:46
well my data set is rather big. 'Votes' and 'Y 'are vectors of length 677. can you suggest a way to share them here? — pegahT, May 08 '21 at 12:18
I think just 40 rows are enough. Read this answer: https://stackoverflow.com/questions/5963269/how-to-make-a-great-r-reproducible-example — Scipione Sarlo, May 08 '21 at 14:17
What do you mean "in opposite direction"? Please clarify what you're expecting exactly. — Calimo, May 10 '21 at 06:57

score 0 · Answer 1 · answered May 09 '21 at 04:43

0

This is the True Positive Rate (of those whom are classified positive how many are actually positive) versus the True Negative Rate (of those whom are classified negative how many are actually negative). The graph makes sense the way it is no?

answered May 09 '21 at 04:43

BBlank

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plotting roc curve in R problem: x axis is in opposite direction

1 Answers1