When we assign work or chores in social units like our workplaces and households, feelings of unfairness are inevitable. While we hope to keep things fair, this can sometimes be difficult to achieve, and we often find ourselves caught in terrible dilemmas. Graduate School of Humanities Assistant Professor THAM Yukari Jessica has been conducting research on the “volunteer’s dilemma,” receiving awards such as the 12th JSPS Ikushi Prize and the 2025 Maenosono Memorial Award for Young Researchers for her paper on feelings of unfairness in work delegation. We asked her about the fundamentals of unfairness, how we can resolve these feelings, the relationship between fairness and well-being, as well as the results of her research and their implications for society.
*This interview was conducted in Japanese and has been translated into English for this article.
Investigating the “volunteer’s dilemma”
You published a paper on the factors impeding fair work delegation in groups. What kind of research did that involve?
Tham:
In my research, I focused on everyday situations in our lives in which someone in a group must perform work that anyone can do—like taking out the trash at home when it’s full or picking up the phone at work. In these situations, if at least one person in the group shoulders the burden, then everyone in the group can reap the benefits.
This type of situation is called the “volunteer’s dilemma,” a type of social dilemma. My research investigates how much work should be undertaken by members of a group in this volunteer’s dilemma when the cost of taking on work differs among group members because, for example, they each have their own strengths and weaknesses.
There are at least two ways to distribute burden. One way is to have the person who is the most proficient at a certain task continue to perform that task forever. This prioritizes efficiency, which minimizes the total burden of the group. Another method involves the more proficient members taking most of the work while having the less proficient members take some as well. This method prioritizes fairness, which uniformly distributes the net burden among the members of the group.
Prioritizing efficiency sacrifices fairness, and vice versa. I investigated which distribution principle is seen as ideal when the two conflict.
Achieving fairness isn’t easy
Specifically, what kind of experiments did you perform in your investigation?
Tham:
Rather than investigating everyday situations, I performed experiments in which participants played an online economic game (figure 1). Between 200 and 300 individuals participated in each experiment, who were then divided into groups of three to play the game. In the game, participants decided whether to incur a cost to pull the lever. If at least one group member pulled the lever, all members received 80 coins. If no one pulled the lever, no one received any coins. I investigated how the participants would react when placed in a situation in which it costs each player a different number of coins to pull the lever, e.g., 30 for player A and 50 each for players B and C. Unable to communicate with each other, participants were repeatedly tasked with deciding between whether to pull the lever or not.
In such a situation, to achieve a fair division of burden, player A (at 30 coins per pull) would have to pull the lever five times in the same span that players B and C pulled three times (at 50 coins per pull). Simply taking turns won’t achieve fairness. Our experiments showed that participants preferred to divide burden fairly, but they often deviated: B and C frequently took on more than was needed to achieve fair burden-sharing.
We also found that the main factor for this divergence was not being able to coordinate among the three group members on who should pull the lever and when. As a result, many groups often relied on a turn-taking rule, causing B and C to shoulder more burden than necessary.
Fair burden sharing is not easy to achieve, especially without mutual coordination. The message I want to convey through this research is that when sharing burdens within a group, it's crucial to communicate and coordinate on who will take on what and when. In any organization, when people don’t coordinate, then it’s very difficult to maintain fairness.
We often blame unfair outcomes on others’ motivation or effort. Instead of attributing them to intent, it’s worth asking whether coordination fell short. This research highlights the role of coordination in a simple context. Next I plan to study more complex, real-world cases.
People dislike unfairness
How did you come to perform this research?
Tham:
My research was inspired by studying experiments using economic games at university. In these experiments, payoffs for both you and your counterpart depend on the actions each of you takes. I was particularly struck by the ultimatum game.
The ultimatum game goes like this. There are two players. Player A receives a certain amount of money and can give as much as they like to player B. If player B accepts the offer, that amount of money is paid out. However, if player B doesn’t accept it, then neither receive any money. For example, suppose that player A is initially given 1000 yen and offers to give player B 400 yen from that. If player B accepts the offer, player A receives 600 yen and player B receives 400 yen. But if player B refuses, neither player gets anything.
A person who doesn’t find it unfair will take even 1 yen since “it’s better than nothing,” but in actuality, getting only 200 or 300 yen would cause them to find it unfair, leading them to decline even if it means neither player receives any money. The first time I heard about the results of that experiment, I once again realized how important fairness is to people. I was attracted to the complexity of the concept of fairness, which led me to want to learn more.
Why fair chore-sharing is so difficult
Why do women tend to take on household chores?
Tham:
In companies, roles are well defined and it’s clear who benefits when work gets done. In households and communities, many chores are the “someone should do it” kind—collectively beneficial but unassigned. I’m researching this problem through the lens of the volunteer’s dilemma.
Homes have a lot to get done, and dividing that work fairly isn’t easy—but it matters more than ever.
Even if a couple shares the same preferences and abilities, assumptions that women like or are better at housework can result in women doing more.
A look at our data suggests preferences are similar across genders, yet the notion that “women enjoy chores” is common among both women and men. I aim to build further evidence.
Relationship between fairness and well-being
Your paper entitled “The importance of examining both the amount and balance of social support: A study on the relationship between social support and subjective well-being of older Japanese adults” was selected to receive the 2025 Maenosono Memorial Award for Young Researchers.
Tham:
When I was working as a part-time researcher at the Tokyo Metropolitan Institute for Geriatrics and Gerontology, I joined a team running a nationwide survey of older adults’ mental and physical health. Drawing on responses from 1,300 people across Japan, we studied the relationship between fair social support and subjective well-being. Using items such as “How much do you help those around you?” and “If someone close to you is in trouble, how much do you help?”, we measured support provided and received and tested their association with life satisfaction.
We found that life satisfaction was highest when support given and received were in balance, underscoring the importance of fairness. While it’s intuitive that over-giving can strain well-being, our results also show that over-receiving can harm it—likely by undermining one’s sense of self-efficacy.
This likely applies not only to older adults but to younger adults, too. If you’re feeling unsatisfied even with ample support, you might be over-reliant on others. Stepping up to help those around you may lift your well-being. Still, while we observed an association between balanced support and well-being, more work is needed to establish whether improving fairness actually causes well-being to improve.
Future directions
Is there any research that you want to pursue even further?
Tham:
“Unfairness” is vague and very complex, changing depending on the situation and what is being distributed or assigned. I hope to clarify it from multiple perspectives.
Conventional research on fairness in social sciences has been using relatively simple situations in experiments, but I’d like to make use of more varied and complex cases in order to provide implications for real-life situations.
The paper on the volunteer’s dilemma I mentioned earlier took into account people’s diversity, but it did not assume tasks' diversity. In reality, both people and tasks are heterogeneous, so “fair” is more complicated. That makes empirical testing harder, but it’s necessary if we’re to deepen our understanding and address people’s sense of unfairness.
Resume
In March 2018, graduated from Hitotsubashi University’s Faculty of Commerce and Management. In March 2020, received her master’s degree in social psychology from the University of Tokyo. In April 2020, became research fellow at the Japan Society for the Promotion of Science. In September 2023, received her doctorate in social psychology from the University of Tokyo. In October 2023, became assistant professor at Kobe University’s Graduate School of Humanities.
Based on the will of the late MAENOSONO Saburo, former professor at Kobe University’s School of Medicine and former director at Kobe Rosai Hospital, the Maenosono Memorial Award for Young Researchers honors the academic achievements of promising young researchers who will serve as Kobe University’s research leaders of the future. Initially established by the Keiai Machizukuri Foundation in 2011 to honor the achievements of researchers at the Graduate School of Medicine, the award has now expanded to honor the achievements of researchers from all graduate schools starting with the award’s 10th iteration.
