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Chapter 12: Q8E (page 722)

Question:If the analysis of variance F-test leads to the conclusion that at least one of the model parameters is nonzero, can you conclude that the model is the best predictor for the dependent variable ? Can you conclude that all of the terms in the model are important for predicting ? What is the appropriate conclusion?

Short Answer

Expert verified

It cannot be concluded if a model parameter is a best predictor for model or it can be concluded if all the term in the model is important just on the basis of F-test.

Step by step solution

01

Step-by-Step Solution Step 1: Best predictor for the dependent variable

It cannot be concluded if a model is the best predictor for the dependent variable y because the F-test leads to the conclusion that at least one of the model parameters is nonzero since it does not compare this model to other models which can be fitted to the data.

02

Overall goodness of the fit

Similarly, it cannot concluded that all the terms in the model are important in predicting just through the F-test because we only know one of the parameters is zero but we do not know if all the parameters are zero.

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