I find that all of our existent reputation economies have serious problems with attribution. Just as a person with a lot of money can easily make more, those who have inflated reputations acquire credit and karma at an accelerated rate and often for things for which they have no rightful claim. As in rollick's point, the only solution is omnipotence or some set of rules that governs the distribution of attribution from a singular, dispassionate perspective (i.e. not from the perspective of the person who blames the waiter for their steak being undercooked, the person who blames the janitor for the filthy bathroom after a herd of Anarchists defiles it deliberately, etc.) At which point, why even defer to humans at all to determine who gets karma?