In: Statistics and Probability
Consider the following two models:
Model 1: E(y) = β0 + β1x1 + β2x2 + β3x3
Model 2: E(y) = β0 + β1x1
Give the null hypothesis for comparing the two models with a best subset (or partial) F-test.
H0: β1 = β2 = β3
H0: β2 = β3 = 0
H0: β1 = 0
Let x1 represent a quantitative independent variable and x2 represent a dummy variable for a 2-level qualitative independent variable. Which of the following models is the equation that produces two parallel curves, one for each level of your QL variable?
E(y) = β0 + β1x1 + β2x12 + β3x2 + β4x1x2 + β5x12x2
E(y) = β0 + β1x1 + β2x12 + β3x2
E(y) = β0 + β1x1 + β3x2