Studies of front-office efficiency in American sport

I was looking for other publications that explored the connection between payroll and performance in other American team sports, and came across this interesting series of articles by ESPN's Patrick Hruby published at the beginning of the year on front-office efficiency in American sports leagues.  He covers the Big Four sports leagues as well as college football and basketball (in the latter cases he uses the athletic department budget figures for either sport). The entire series is worth reading.

A similar analysis in European sport would be very illuminating, but payroll information appears to be tightly guarded by the football clubs throughout Europe.