在插入符 (R) 中如何将两个 class 概率得分列合并为一个 "predict(model,test_set,type="prob 之后的概率 Class 列")"

Question

我想将两个概率得分列合并为一个概率得分列（见下图）

mtcars
library(caret)
#print(colnames(dat))
set.seed(7117)
ind <- createDataPartition(mtcars$am, p = .7, list = FALSE)
train_set <- mtcars[ind, ]
test_set <- mtcars[-ind, ]

train_set
test_set



###################################################################################################
train_ctrl = trainControl(
  method  = "cv", #Specifying Cross validation
  number  = 3 # Specifying 3-fold # 
)

set.seed(40198)
model <- train(as.factor(am) ~ .,
               data = train_set, 
               method = "rf",
               trControl = train_ctrl,
               # linout = T,
               preProc = c("center", "scale"))
model
# need help after `predict(model,test_set,type="prob")`
Prob_score <- predict(model,test_set,type="prob") # returns probability of both '0' and '1' classes, I want a consolidated Probability score of corresponding class  

Pred_Class<-predict(model,test_set)

df <-cbind(Pred_Class,Prob_score)

期望的输出

#而不是第 0 列和第 1 列，我只想 return ONE 与下图中突出显示的 Pred_Class 相对应的概率列。

Answer 1

我不确定为什么我不能用相同的种子得到你的输出，但这是你最后一行代码的输出：

cbind(Pred_Class,Prob_score)
                   Pred_Class     0     1
Hornet 4 Drive              0 0.824 0.176
Duster 360                  0 0.916 0.084
Merc 450SL                  0 0.986 0.014
Merc 450SLC                 0 0.978 0.022
Cadillac Fleetwood          0 0.994 0.006
Toyota Corona               1 0.322 0.678
Camaro Z28                  0 0.758 0.242
Ford Pantera L              0 0.602 0.398
Ferrari Dino                1 0.308 0.692

您可以使用apply(..,1,..)取每一行的最大值：

data.frame(Pred_Class,prob = apply(Prob_score,1,max))

                   Pred_Class  prob
Hornet 4 Drive              0 0.824
Duster 360                  0 0.916
Merc 450SL                  0 0.986
Merc 450SLC                 0 0.978
Cadillac Fleetwood          0 0.994
Toyota Corona               1 0.678
Camaro Z28                  0 0.758
Ford Pantera L              0 0.602
Ferrari Dino                1 0.692

在插入符 (R) 中如何将两个 class 概率得分列合并为一个 "predict(model,test_set,type="prob 之后的概率 Class 列")"

In Caret (R) How to consolidate two class probability score columns to one Probability Class column after "predict(model,test_set,type="prob")"

r

r-caret