A commitment device is, according to journalist Stephen J. Dubner and economist Steven Levitt, "a means with which to lock yourself into a course of action that you might not otherwise choose but that produces a desired result". Put differently, a commitment device is a "way to change one's own incentives to make an otherwise empty promise credible". It is a technique where someone makes it easier for themselves to avoid akrasia (acting against one's better judgment), particularly procrastination.
The term "commitment device" is used in both economics and game theory. In particular, the concept is relevant to the fields of economics and especially the study of decision making (Brocas, et al.). "Commitment devices are a way to overcome the discrepancy between an individual's short-term and long-term preferences; in other words, they are a way for self-aware people to modify their incentives or set of possible choices in order to overcome impatience or other irrational behavior. You know the story of Ulysses tying himself to the mast so that he couldn't be lured in by the song of the Sirens? You can think of that as the quintessential commitment device" (Beggs 2009).
- Create larger obstacles to temptations to increase the costs of temptations.
- Make it well known of your commitment, thus putting your reputation on the line.
- Make a monetary contract with someone to increase the benefit of staying on course.
Examples of commitment devices abound. Dubner and Levitt give the example of Han Xin, a general in Ancient China, who positioned his soldiers with their backs to a river, making it impossible for them to flee, thereby leaving them no choice but to attack the enemy head-on. They also present various commitment devices related to weight loss (2007). In addition, some game theorists have argued that human emotions and sense of honor are forms of commitment device (Arslan 2011 & Ross and Dumouchel 2004). Other examples include announcing commitments publicly and mutually assured destruction (Straker 2011), as well as software programs that block internet access for a predetermined period of time.
Other cited literature
Arslan, Ruben. "Evolution of cooperation: Emotion as a commitment device," Evolutionary Theory across the Life Sciences, 2000-2011. http://itb.biologie.hu-berlin.de/blogs/evoblog/contrib/evolution-of-cooperation-emotion-as-a-commitment-device-1
Beggs, Jodi. "Be Careful With Those Commitment Devices…," June 17, 2009. Online at http://www.economistsdoitwithmodels.com/2009/06/17/be-careful-with-those-commitment-devices/
Brocas et al., Isabelle, Juan D. Carrillo, and Mathias Dewatripont. "Commitment Devices under Self-Control Problems: An Overview," Online at http://www-bcf.usc.edu/~juandc/PDFpapers/book2-ch04.pdf
Ross and Dumouchel, Don and Paul. "Emotions as Strategic Signals," Rationality and Society August 2004 vol. 16 no. 3 251-286. Online at http://rss.sagepub.com/content/16/3/251.abstract
Straker, Dave. "Commitment Devices," Changing Minds, 2002-2011. Online at http://changingminds.org/techniques/general/more_methods/commitment_devices.htm