An acquaintance of mine was working on an accounting PhD on basically this subject (trying to quantify CEO contribution to revenues and profits, all else held e

An acquaintance of mine was working on an accounting PhD on basically this subject (trying to quantify CEO contribution to revenues and profits, all else held equal). He said that after years studying it, he thought it's too noisy with too little data over too long a timeframe to do a good quantitative analysis. He also pointed out there is a big "apples to oranges" problem even with the limited data available. In sports (but not business) you have lots of reliably tracked micro metrics in addition to final metrics (wins/revenue). The micro metrics are generated regularly (stats for each player for each game) and those metrics are portable across players (everyone is going for points, runs, blocks, whatever). In comparison, for CEOs you mainly have quarterly reporting of coarse financials (but nothing like employee morale, number of offices opened, etc.).