When applying the lm function as follows (the assumptions were not considered. The purpose of this example is just to make my question clear) :
library(carData)
model1 = lm(data = carData::Salaries,salary~sex+yrs.service+yrs.since.phd)
and comparing it with the model created with the function caret::train() (method = "lm") :
library(caret)
mycontrol = trainControl(method = "CV",number=10,)
model2 = train(salary~sex+yrs.service+yrs.since.phd,
data = Salaries,
method = "lm",
trControl=mycontrol)
The outcomes of the two models are the same. why ? and in that case what is the purpose of applying the cross validation method in order to create a linear regression model ?
summary(model1)
summary(model2)