1 1. Arbol con UN regresor

library(tree)

datos = read.table('coches.txt',header=T)

t1 = tree(consumo~cv,data=datos)
plot(t1)
text(t1,pretty=0)

plot(datos$cv,datos$consumo,xlab="CV",ylab="Consumo")
partition.tree(tree=t1, add = TRUE, col = "red", lwd = 3)

2 2. Arbol con DOS regresores

t2 = tree(consumo ~ cv + peso,data=datos)
plot(t2)
text(t2,pretty=0)

plot(datos$cv, datos$peso, xlab="CV", ylab="Peso")
partition.tree(tree=t2, label = "Consumo", add = TRUE, ordvars = c("cv","peso"), col = "blue")

3 3. Graficos mas bonitos con rpart

library(rpart)
library(rpart.plot)

t11 <- rpart(consumo ~ cv + peso, data = datos, method = "anova")
rpart.plot(x = t11, yesno = 2, extra = 0, digits = 3)