Effort expenditure decreases risk aversion when dealing with gains but not losses

Separate lines of research suggest that people tend to avoid mental effort, but also value it. Evidence for this effort paradox in the same context is scarce. We tested whether people discount effort prior to the investment of effort and value effort following its investment. In three preregistered experiments (total N = 450), participants repeatedly chose between executing a low-effort task for a small reward and a high-effort task for a larger reward. Participants then chose whether or not to gamble with their rewards. As people tend to become more risk averse as subjective value increases, we reasoned that participants would be less likely to gamble with rewards the harder they had to work for them. In Studies 1 and 2, we framed the experiment in terms of gaining rewards. In Study 3, we framed the experiment in terms of losing rewards. In all three studies, effort was discounted prospectively, meaning people demanded higher rewards to invest more effort. Contrary to our predictions, we found that people were more likely to gamble with the rewards the more effort it required to obtain them, but only when the rewards were framed in terms of gains (Studies 1 and 2). Collectively, these results suggest that any potential effort paradox is unlikely to occur when people are aware of the association between investing effort and gaining rewards. Our results also imply a novel hypothesis, namely that the aversive feeling accompanying effort might motivate people to engage in risky behavior.

众多研究指出，人们在避免心理努力的同时，亦对其抱有珍视之情。在同一语境下，关于这一努力悖论的证据寥寥无几。本研究旨在探究人们在投入努力之前是否会对努力进行折价，以及投入努力之后是否会对努力赋予价值。在三项预先注册的实验（总计参与人数 N = 450）中，参与者需要在执行低努力任务以获得小奖励和执行高努力任务以获得大奖励之间进行选择。随后，参与者需决定是否愿意以他们的奖励进行赌博。鉴于人们倾向于随着主观价值的提升而变得更加风险规避，我们推断，参与者越难以获得奖励，他们进行赌博的可能性就越低。在研究 1 和 2 中，我们将实验框架设定为获取奖励。在研究 3 中，我们将实验框架设定为失去奖励。在所有三项研究中，努力均被预期性折价，即人们要求更高的奖励以投入更多的努力。与我们的预测相反，我们发现，当获得奖励所需的努力越多时，人们进行赌博的可能性越大，但仅当奖励被设定为收益时（研究 1 和 2）。综合这些结果，表明当人们意识到投入努力与获得奖励之间的关联时，任何潜在的努力悖论均不太可能发生。我们的结果还暗示了一个新的假设，即伴随努力的厌恶感可能激发人们从事风险行为的动机。