In 1968 Knox and Inkster,[REF] in what is perhaps the classic sunk cost experiment, approached 141 horse bettors: 72 of the people had just finished placing a $2.00 bet within the past 30 seconds, and 69 people were about to place a $2.00 bet in the next 30 seconds.
Similar results have been obtained in earlier studies by Staw (1974, 1976) and by Arkes and Blumer (1985)[REF] and Whyte (1986) [REF].