使用 `ctree` 包运行 `party`，列作为因子而不是字符

Question

我已提及convert data.frame column format from character to factor和 Converting multiple data.table columns to factors in R和 Convert column classes in data.table

不幸的是，它没有解决我的问题。我正在使用 bodyfat 数据集，我的数据框称为 > bf。我添加了一个名为agegrp的列来将不同年龄的人分类为年轻、中年或老年:

bf$agegrp<-ifelse(bf$age<=40, "young", ifelse(bf$age>40 & bf$age<55,"middle", "old"))

这是ctree分析:

> set.seed(1234)
> modelsample<-sample(2, nrow(bf), replace=TRUE, prob=c(0.7, 0.3))
> traindata<-bf[modelsample==1, ]
> testdata<-bf[modelsample==2, ]
> predictor<-agegrp~DEXfat+waistcirc+hipcirc+kneebreadth` and ran, `bf_ctree<-ctree(predictor, data=traindata)
> bf_ctree<-ctree(predictor, data=traindata)

我收到以下错误:

Error in trafo(data = data, numeric_trafo = numeric_trafo, factor_trafo = factor_trafo,  : 
  data class character is not supported
In addition: Warning message:
In storage.mode(RET@predict_trafo) <- "double" : NAs introduced by coercion

由于 bf$agegrp 属于我运行的“字符”类，

> bf$agegrp<-as.factor(bf$agegrp)

agegrp 列现在被强制转换为因子。

> 类 (bf$agegrp) 给出 [1]“因子”。

我尝试再次运行ctree，但它抛出了相同的错误。有谁知道问题的根本原因是什么？

Answer 1

这对我有用:

library(mboot)
library(party)
bf <- bodyfat
bf$agegrp <- cut(bf$age,c(0,40,55,100),labels=c("young","middle","old"))
predictor <- agegrp~DEXfat+waistcirc+hipcirc+kneebreadth

set.seed(1234)
modelsample <-sample(2, nrow(bf), replace=TRUE, prob=c(0.7, 0.3))
traindata   <-bf[modelsample==1, ]
testdata    <-bf[modelsample==2, ]
bf_ctree    <-ctree(predictor, data=traindata)
plot(bf_ctree)