Multiple varying coefficients: (a) Repeat the previous exercise, this time allowing the coefficient for income to vary by state as well. (b) Repeat, allowing all the coefficients to vary by state. (c)...

Multiple varying coefficients:

(a) Repeat the previous exercise, this time allowing the coefficient for income to vary by state as well.

(b) Repeat, allowing all the coefficients to vary by state. (c) Summarize your inferences from these models graphically.