我是R中的新玩家,想解决二进制分类任务。
数据集有两个类的因子变量标签:first-0,second-1。下一张图片显示了它的实际头部:
TimeDate列-它只是索引。
类分布定义为:
print("the number of values with % in factor variable - LABELS:")
percentage <- prop.table(table(dataset$LABELS)) * 100
cbind(freq=table(dataset$LABELS), percentage=percentage)
班级分布结果:
另外,我知道slot2列是根据以下公式计算的:
Slot2 = Var3 - Slot3 + Slot4
在分析相关矩阵的基础上,选择特征var1、var2、var3、var4。
在开始建模之前,我将数据集划分为训练和测试部分。
我尝试使用下一个代码为二进制分类任务构建随机林模型:
rf2 <- randomForest(LABELS ~ Var1 + Var2 + Var3 + Var4,
data=train, ntree = 100,
mtry = 4, importance = TRUE)
print(rf2)
结果是:
Call:
randomForest(formula = LABELS ~ Var1 + Var2 + Var3 + Var4,
data = train, ntree = 100, mtry = 4, importance = TRUE)
Type of random forest: classification
Number of trees: 100
No. of variables tried at each split: 4
OOB estimate of error rate: 0.16%
Confusion matrix:
0 1 class.error
0 164957 341 0.002062941
1 280 233739 0.001196484
当我试图预测:
p1 <- predict(rf2, train, type="prob")
print("Prediction & Confusion Matrix - train data")
confusionMatrix(p1, train$LABELS)
p2 <- predict(rf2, test, type="prob")
print("Prediction & Confusion Matrix - test data")
confusionMatrix(p2, test$LABELS)
我在r中收到一个错误:
[1] "Prediction & Confusion Matrix - train data"
Error: `data` and `reference` should be factors with the same levels.
Traceback:
1. confusionMatrix(p1, train$LABELS)
2. confusionMatrix.default(p1, train$LABELS)
3. stop("`data` and `reference` should be factors with the same levels.",
. call. = FALSE)
另外,我已经试着用以下问题中的idea来解决它:
-
Error in ConfusionMatrix the data and reference factors must have the same number of levels R CARET
-
Error in Confusion Matrix : the data and reference factors must have the same number of levels
但这对我没有帮助。
你能帮我解决这个错误吗?
如有任何意见和建议,我将不胜感激。提前谢谢。