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wiki:kappar

Plotting a confusion matrix and calculate kappa statistics

generate simulated data

library(PresenceAbsence)
     set.seed(666)
     N=1000
N
     SIMDATA<-matrix(0,N,3)
str(SIMDATA)
     SIMDATA<-as.data.frame(SIMDATA)
str(SIMDATA)
     names(SIMDATA)<-c("plotID","Observed","Predicted")
     SIMDATA$plotID<-1:N
str(SIMDATA)
     SIMDATA$Observed<-rbinom(n=N,size=1,prob=.2)
str(SIMDATA)
     SIMDATA$Predicted[SIMDATA$Observed==1]<-rnorm(n=length(SIMDATA$Observed[SIMDATA$Observed==1]),mean=.8,sd=.15)
     SIMDATA$Predicted[SIMDATA$Observed==0]<-rnorm(n=length(SIMDATA$Observed[SIMDATA$Observed==0]),mean=.2,sd=.15)
     SIMDATA$Predicted<-(SIMDATA$Predicted-min(SIMDATA$Predicted))/(max(SIMDATA$Predicted)-min(SIMDATA$Predicted))
 
     ### plot simulated data
     hist(SIMDATA$Predicted,100)
     hist(SIMDATA$Observed,100)
     ### calculate confusion matrix ###
     confusion.matrix=cmx(SIMDATA)
     Kappa(confusion.matrix, st.dev = TRUE)
 
data(SIM3DATA)
 
     cmx(SIM3DATA)
     cmx(SIM3DATA,which.model=2)
     cmx(SIM3DATA,which.model=3,threshold=.2)
wiki/kappar.txt · Last modified: 2017/12/05 22:53 (external edit)