Nolan McCarty on the super-committee:
Given the degree of polarization in Congress, the most obvious way to manipulate the composition to improve the likelihood of success would be to appoint a SC with more moderates and fewer ideologues than the Congress itself. Of course, given the appointment structure (with party leaders making unilateral appointments), this was not likely to happen. And it didn’t happen. Using Keith Poole’s “common space” estimates, I find that the standard deviation of the SC’s ideal points were .507 compared to the standard deviation in the combined House and Senate of .437. So the appointments mechanism actually increased polarization. Just to underscore that the inflated polarization was no accident or statistical fluke, I randomly drew 1000 twelve-member SCs from the membership of the House and Senate. Only 90 of these had standard deviations larger than the one our leaders actually gave us.
More here.