SAS practice, use the Health data, compare the following models to answer the question.

Model 1: Exphlth =bo + b1 Income + b2 seniors +e

Model 2: HLT_percapita = bo + b1inc_percapita+b2 seniors +e

Choose the best option to answer the question:

I. Models 1 and 2 violate this classical assumption: the regression model is linear, is correctly specified, and has an additive error term.

II. Models 1 and 2 are the best models to predict aggregate expenditures on health care.

III. The percentage of seniors in the population is an important predictor in both models.

IV. The parameter estimates of model 2 should be interpreted as % because of the ratio variables.