Favoritism in asymmetric contests: Head starts and handicaps

► Asymmetric all-pay auction with incomplete information. ► Head starts, handicaps, or a combination can be used to improve revenue or welfare. ► The instruments are not equivalent, it pays to combine them. ► With large asymmetry, the weak bidder should be given a head start and a handicap. ► It may be possible to make both bidders better off ex ante.