Regression coefficient is zero I am trying to construct a quadratic regression model for a data a

Yesenia Obrien 2022-07-03 Answered
Regression coefficient is zero
I am trying to construct a quadratic regression model for a data as
Y = α 0 + α 1 X 1 + α 2 X 2 + α 3 X 1 X 2 + α 4 X 1 2 + α 5 X 2 2
I am getting coefficient of X 1 2 ( α 4 ) = 0.00000006 0.. How can we interpret this model for X 1 2 term? What is the impact of α 4 = 0 for the model? Adjusted R 2 = 0.9988
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Answers (1)

engaliar0l
Answered 2022-07-04 Author has 13 answers
It implies that there is no quadratic relationship between X 1 and Y given ( X 1 , X 2 , X 1 X 2 , X 2 2 ), thus the best approximation of the true process with the variables ( X 1 , X 2 , X 1 X 2 , X 1 2 , X 2 2 ) is
Y = α 0 + α 1 X 1 + α 2 X 2 + α 3 X 1 X 2 + α 5 X 2 2
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