I would really appreciate any help that I can get with these to questions.
Why do economists pay more attention to national economies than state or regional economies?
What factors might contribute to a low level of productivity in an economy? Compare these to the rapid productivity growth experienced by the United States during the 1990s.
There are probably several reasons why economists focus mainly on national economies. The primary one, though, is probably statistical in nature. Economics, likes most social sciences, relies mainly on statistics. Statistics work well are large populations, but poorly when smaller numbers are involved. This is because it's based on averages, and the average of a large population is less likely to be affected by anomalies. For example, in a particular region, you might see odd things, like invasive species or an outbreak of measles. ...
Factors contributing to productivity; regional vs national economics