我用R caret训练了一颗树模型,现在尝试生成混淆矩阵时一直出现以下错误:
Error in confusionMatrix.default(predictionsTree, testdata$catgeory) : the data and reference factors must have the same number of levels
prob <- 0.5 #Specify class split
singleSplit <- createDataPartition(modellingData2$category, p=prob,
times=1, list=FALSE)
cvControl <- trainControl(method="repeatedcv", number=10, repeats=5)
traindata <- modellingData2[singleSplit,]
testdata <- modellingData2[-singleSplit,]
treeFit <- train(traindata$category~., data=traindata,
trControl=cvControl, method="rpart", tuneLength=10)
predictionsTree <- predict(treeFit, testdata)
confusionMatrix(predictionsTree, testdata$catgeory)
在生成混淆矩阵时出现了错误。这两个对象的级别是相同的。我无法弄清楚问题所在。它们的结构和级别如下。
它们应该是相同的。如果有帮助,将不胜感激,因为这让我崩溃了!!
> str(predictionsTree)
Factor w/ 30 levels "16-Merchant Service Charge",..: 28 22 22 22 22 6 6 6 6 6 ...
> str(testdata$category)
Factor w/ 30 levels "16-Merchant Service Charge",..: 30 30 7 7 7 7 7 30 7 7 ...
> levels(predictionsTree)
[1] "16-Merchant Service Charge" "17-Unpaid Cheque Fee" "18-Gov. Stamp Duty" "Misc" "26-Standard Transfer Charge"
[6] "29-Bank Giro Credit" "3-Cheques Debit" "32-Standing Order - Debit" "33-Inter Branch Payment" "34-International"
[11] "35-Point of Sale" "39-Direct Debits Received" "4-Notified Bank Fees" "40-Cash Lodged" "42-International Receipts"
[16] "46-Direct Debits Paid" "56-Credit Card Receipts" "57-Inter Branch" "58-Unpaid Items" "59-Inter Company Transfers"
[21] "6-Notified Interest Credited" "61-Domestic" "64-Charge Refund" "66-Inter Company Transfers" "67-Suppliers"
[26] "68-Payroll" "69-Domestic" "73-Credit Card Payments" "82-CHAPS Fee" "Uncategorised"
> levels(testdata$category)
[1] "16-Merchant Service Charge" "17-Unpaid Cheque Fee" "18-Gov. Stamp Duty" "Misc" "26-Standard Transfer Charge"
[6] "29-Bank Giro Credit" "3-Cheques Debit" "32-Standing Order - Debit" "33-Inter Branch Payment" "34-International"
[11] "35-Point of Sale" "39-Direct Debits Received" "4-Notified Bank Fees" "40-Cash Lodged" "42-International Receipts"
[16] "46-Direct Debits Paid" "56-Credit Card Receipts" "57-Inter Branch" "58-Unpaid Items" "59-Inter Company Transfers"
[21] "6-Notified Interest Credited" "61-Domestic" "64-Charge Refund" "66-Inter Company Transfers" "67-Suppliers"
[26] "68-Payroll" "69-Domestic" "73-Credit Card Payments" "82-CHAPS Fee" "Uncategorised"
identical(levels(predictionsTree),levels(testdata$category))
的输出是什么? - fxicatgeory
,检查length(testdata$category)
和length(predictionsTree)
,同时检查两个向量的摘要。如果您只想要一个简单的混淆矩阵:table(predictionsTree,testdata$category)
。 - fxi