Dear R fans, I am trying to do step-wise linear regression using the F-test to decide which variables to admit. Ewout Steyerberg suggests using the F-test for this purpose.
I first build a model using no variables using lm(y ~ 1) and then using one variable that is a strong predictor using lm(y ~ x). When I call var.test on these two models, I do not get a significant p-value0.07. But a summary of the second model gives a F-test p-value that is very small. My questions are: Should I be using var.test to run the F-test to decide which variable to add next? What is the difference between the F-test run by var.test and summary.lm? Has step-wise model building using the F-test been programmed already? Thanks! Troy [[alternative HTML version deleted]]
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