Here's an interview with HBS's Joshua Coval about measuring the correlation between congressional power and railroading taxpayer dollars into one's state or district.

Q: One of your findings was that the chairs of powerful congressional committees truly bring home the bacon to their states in the forms of earmark spending. Can you give a sense of how large this effect is?

A: Sure. The average state experiences a 40 to 50 percent increase in earmark spending if its senator becomes chair of one of the top-three committees. In the House, the average is around 20 percent.

HT Marginal Revolution.