There is great data on individual representatives going back decades which, one presumes, represent their districts. Look into Poole and Rosenthal's d-Nominate data here and see their book
http://voteview.uh.edu/default.htm Alex -- Dr. Alexander Tabarrok Vice President and Director of Research The Independent Institute 100 Swan Way Oakland, CA, 94621-1428 Tel. 510-632-1366, FAX: 510-568-6040 Email: [EMAIL PROTECTED]
