Question

5. A researcher estimates the effect of crime rates on spending on police by using city-level data. Explain how simultaneous causality might invalidate the results.

6. Suppose that a state offered voluntary standardized tests to all its third graders and that these data were used in a study of class size on student performance. Explain how sample selection bias might invalidate the results.

7. Four hundred driver’s license applicants were randomly selected and asked whether they passed their driving test (Pass=1) or failed their test (Pass=0). And the estimated model is as follows. Note that experience is measured in years. Interpret the coefficient of Experience. ???? ̂ = 0.712 + 0.031?????????�

Answer 1