Consider the following model Y i = 1 + 2 D i + X i + u i where Y = annual salary

Consider the following model

Y_i = α₁ + α₂D_i + βX_i + u_i

where Y = annual salary of a college professor

X = years of teaching experience

D = dummy for gender

Consider three ways of defining the dummy variable.

a. D = 1 for male, 0 for female.

b. D = 1 for female, 2 for male.

c. D = 1 for female, −1 for male.

Interpret the preceding regression model for each dummy assignment. Is one method preferable to another? Justify your answer.