Most People Keep Their Word Rather Than Their Money

Abstract

Promises are crucial for human cooperation because they allow people to enter into voluntary commitments about future behavior. Here we present a novel, fully incentivized paradigm to measure voluntary and costly promise-keeping in the absence of external sanctions. We found across three studies ( N = 4,453) that the majority of participants (61%–98%) kept their promises to pay back a specified amount of a monetary endowment, and most justified their decisions by referring to obligations and norms. Varying promise elicitation methods (Study 1a) and manipulating stake sizes (Study 2a) had negligible effects. Simultaneously, when others estimated promise-keeping rates (using two different estimation methods), they systematically underestimated promise-keeping by up to 40% (Studies 1b and 2b). Additional robustness checks to reduce potential reputational concerns and possible demand effects revealed that the majority of people still kept their word (Study 3). Promises have a strong normative power and binding effect on behavior. Nevertheless, people appear to pessimistically underestimate the power of others’ promises. This behavior–estimation gap may prevent efficient coordination and cooperation.

Keeping them honest: Promises reduce cheating in adolescents

“…Moreover, the effect of promises remained stable when we introduced a negative externality (Study 2) or incentivized intergroup competition (Study 3). Overall, this confirms that promises have a strong, binding effect on behavior and extends previous findings with MTurk workers that kept their promise at a cost to themselves (Woike & Kanngiesser, 2019). Promises can thus be a powerful intervention to promote desirable behaviors (Bicchieri, 2002; Kulik & Carlino, 1987; Ostrom et al, 1992; Wang & Katzev, 1990) and to curb dishonesty.…”

“…Irrespective of the different stances, research has consistently found that many people will keep their word—even at a cost to themselves (Woike & Kanngiesser, 2019)—and that promises can promote desirable behaviors in children and adults such as cooperation, helping, recycling, or visits to doctors (Bicchieri, 2002; Charness & Dufwenberg, 2006; Ellingsen & Johannesson, 2004; Kanngiesser, Köymen, & Tomasello, 2017; Kulik & Carlino, 1987; Ostrom, Walker, & Gardner, 1992; Wang & Katzev, 1990). Promises to tell the truth become effective in children from 5 to 6 years of age.…”

“…Comparing reported outcomes in the promise condition and the control condition allowed us to estimate the effectiveness of the promise intervention. A similar design was recently implemented in a different task with US participants (Woike & Kanngiesser, 2019). Instructions in the control condition made no reference to truth telling and, arguably, did not make it explicit that cheating would be an option (Kajackaite & Gneezy, 2017).…”

Nonverbal content and trust: An experiment on digital communication

“…Furthermore, we also find evidence 5 See, for instance, Charness and Dufwenberg (2006); Vanberg (2008); Ismayilov and Potters (2016); Schwartz et al (2019). For a systematic review of the experimental literature on promise-making, see Woike and Kanngiesser (2019). Other characteristics of messages may also matter.…”

Nonverbal Content and Swift Trust: An Experiment on Digital Communication

“…Adding nonverbal 5 See, for instance, Charness and Dufwenberg (2006); Vanberg (2008); Ismayilov and Potters (2016);Schwartz et al (2019). For a systematic review of the experimental literature on promise-making, see Woike and Kanngiesser (2019). Other characteristics of messages may also matter.…”