4. An economist is analyzing the relationship between disposable income and food expenditure for the citizens of a developing country. A survey of the citizens has been taken, and data have been collected on income and food expenditures. The following statistical model is postulated for the data:

Yi ¼ b1 z b2 i eei

;

where yi ¼ expenditure on food for the ith household;

Zi ¼ disposable income for the ith household; and ei 0

s ~ iid N(0,s2

)

(a) Transform the model into the GLM form. What parameters or functions of parameters are being estimated by the least-squares estimator applied to the transformed model?

(b) Is the least-squares estimator unbiased, the BLUE, and/or the MVUE for the parameters or functions of parameters being estimated?