Problem
1. In his study of the effect of incarceration on crime rates, suppose that Levitt had used the number of lawyers per capita as an instrument. Is this instrument relevant? Is it exogenous? Is it a valid instrument?
2. In their study of the effectiveness of cardiac catheterization, McClellan, McNeil, and Newhouse (1994) used as an instrument the difference in distance to cardiac catheterization and regular hospitals. How could you deter-mine whether this instrument is relevant? How could you determine whether this instrument is exogenous?
The response should include a reference list. Double-space, using Times New Roman 12 pnt font, one-inch margins, and APA style of writing and citations.