In public good games, voluntary contributions tend to start off high and decline as the game is repeated. If high contributors are matched, however, contributions tend to stay high. We propose a formalization predicting that high contributors will self-select into groups committed to charitable...

Recent literature has shown that all-pay auctions raise more money for charity than winner-pay auctions. We demonstrate that the first and second-price winner-pay auctions generate higher revenue than first-price all-pay auctions when bidders are sufficiently asymmetric. To prove it, we consider...