caret (version 5.07-001)

plotObsVsPred: Plot Observed versus Predicted Results in Regression and Classification Models

Description

This function takes an object (preferably from the function extractPrediction) and creates a lattice plot. For numeric outcomes, the observed and predicted data are plotted with a 45 degree reference line and a smoothed fit. For factor outcomes, a dotplot plot is produced with the accuracies for the different models. If the call to extractPrediction included test data, these data are shown, but if unknowns were also included, they are not plotted

Usage

plotObsVsPred(object, equalRanges = TRUE, ...)

Arguments

Value

  • A lattice object. Note that the plot has to be printed to be displayed (especially in a loop).

Examples

Run this code
# regression example
data(BostonHousing)
rpartFit <- train(BostonHousing[1:100, -c(4, 14)], 
                  BostonHousing$medv[1:100], 
                  "rpart", tuneLength = 9)
plsFit <- train(BostonHousing[1:100, -c(4, 14)], 
                BostonHousing$medv[1:100], 
                "pls")

predVals <- extractPrediction(list(rpartFit, plsFit), 
                              testX = BostonHousing[101:200, -c(4, 14)], 
                              testY = BostonHousing$medv[101:200], 
                              unkX = BostonHousing[201:300, -c(4, 14)])

plotObsVsPred(predVals)


#classification example
data(Satellite)
numSamples <- dim(Satellite)[1]
set.seed(716)

varIndex <- 1:numSamples

trainSamples <- sample(varIndex, 150)

varIndex <- (1:numSamples)[-trainSamples]
testSamples <- sample(varIndex, 100)

varIndex <- (1:numSamples)[-c(testSamples, trainSamples)]
unkSamples <- sample(varIndex, 50)

trainX <- Satellite[trainSamples, -37]
trainY <- Satellite[trainSamples, 37]

testX <- Satellite[testSamples, -37]
testY <- Satellite[testSamples, 37]

unkX <- Satellite[unkSamples, -37]

knnFit  <- train(trainX, trainY, "knn")
rpartFit <- train(trainX, trainY, "rpart")

predTargets <- extractPrediction(list(knnFit, rpartFit), 
                                 testX = testX, 
                                 testY = testY, 
                                 unkX = unkX)

plotObsVsPred(predTargets)

Run the code above in your browser using DataCamp Workspace