Which employee deserves the highest salary? Should a professor receive tenure? Did my spouse do their fair share of the household chores?
These types of questions all require people to pass judgment on the effort expended by others. According to a recent study in Scientific Reports, people view the rewards others receive as a proxy for effort—and those with conservative political leanings, according to the results, are particularly likely to incorporate rewards into their judgment about how hard someone else has worked.
“When we judge someone else’s effort, we rely on reward information, because we are very uncertain,” says Max Rollwage, a cognitive neuroscientist at University College London, United Kingdom, and the study’s first author. “This effect that we observed in a lab setting … seems to be related to broader attitudes about our society, and how rewards and efforts are related.”
These sorts of judgments happen all of the time, with serious social implications. For example, people who are perceived to work hard on group tasks are well-liked, while free riders—those who eschew hard work but reap the rewards a group earns—are despised.
Estimating effort is a difficult task even for the one expending that effort. Rollwage’s former adviser, cognitive neuroscientist Arezoo Pooresmaeili of the European Neuroscience Institute in Göttingen, Germany, had already shown in 2015 that a person’s perception of their own effort could be influenced by receiving a reward. When Rollwage was working at the Institute, the team hypothesized that rewards would also assist people in judging another person’s effort.
To test this in the lab, they partnered participants together and asked them to take turns rolling a digital ball up a ramp. To roll the ball on the computer screen, the player had to push the left and right arrows of the keyboard, alternately and quickly, before the ball rolled back down. Then, the player was given a reward of up to 10 euro cents commensurate with the difficulty of the task, which varied depending on the virtual “gravity” pulling the ball back down onscreen.
After learning about the reward value, the person who had just played rated their effort on a slider bar, as did their partner who had observed. With data from 51 subjects, the authors found that when a person received a high reward, they rated their own effort higher. The effect was even more pronounced when rating their partner’s efforts.
To pick apart the cognitive process further, Rollwage tested several computational models that represented how a player or observer might estimate effort, incorporating not only the raters’ own observations of key presses and successes as the task took place, but also the reward the subject received. They found the brain worked in a manner known as Bayes-optimal, weighting the two factors based on the person’s perception of their reliability.
“It is a rational bias,” says Pooresmaeili, a coauthor on the current study. Lacking full understanding of the other person’s effort, or even their own, people turned to the reward for additional information.
But doing so could have unfair consequences. For example, people might assume that gender inequalities related to salary correspond to workers’ efforts rather than other factors, or that poorer people simply haven’t worked hard enough. “Out in the wild … we probably actually rely way more on reward information,” says Rollwage.
The authors also hypothesized that sociopolitical leanings would affect how much a person relies on rewards when judging effort. In general, people with a self-reported conservative world view tend to accept the status quo and the social hierarchy therein, notes Rollwage. “And maybe the belief that the distribution of wealth, or how much money people are earning, is strictly defined by their effort,” adds Pooresmaeili. Before the ball rolling, subjects completed a questionnaire to assess their political leanings. The researchers found that the stronger a person’s conservatism, the more weight they gave to the rewards.
While it’s not always appropriate to apply lab-based results to real-world situations, it makes sense that people consider rewards when judging others, according to Patricia Lockwood, a cognitive neuroscientist at the University of Oxford, United Kingdom, who wasn’t involved in the study. “There are many examples in everyday life where we probably engage in that kind of process,” she says. For example, in the home, “We always think that we do far more chores than our partner.”
Lockwood thinks there’s potential to alter those reward-based biases, if people are made aware of them. “I’d like to think,” she says, “these things can be changed.”