Two lecturers from the Department of Economics, Faculty of Economics and Business, Universitas Gadjah Mada (FEB UGM), Dr. Muhammad Ryan Sanjaya and Amanda Wijayanti, M.S., have contributed to an international research project published in the prestigious scientific journal Proceedings of the National Academy of Sciences on March 20, 2026.
The study, titled “The Private Solution Trap in Collective Action Problems Across 34 Nations,” reveals the phenomenon of the private solution trap, which refers to individuals’ tendency to choose independent solutions rather than engage in collective action when addressing global challenges. Led by the University of Nottingham, the research involved 72 economists and psychologists from various countries. Conducted across 34 nations, including Indonesia, the study is highly relevant to global issues such as climate change, public health, and infrastructure development, all of which require collective action.
The FEB UGM team collaborated with Dr. Eugene Malthouse from the University of Nottingham (UK) and Dr. Katharina Werner from the University of Passau (Germany).
Amanda Wijayanti explained that the laboratory experiment involved 268 participants. They were placed in small-group collective risk game scenarios, where they had to decide whether to solve problems individually or cooperate with others. Each participant was given a set of resources to allocate toward either private or public solutions.
“Specifically, this study examines whether individuals who believe that success primarily comes from hard work are more likely to rely on self-reliance and private problem-solving rather than collective action,” Amanda stated.
The findings reveal a paradox. On one hand, participants believe that wealthier individuals should contribute more to solving collective problems. On the other hand, groups with greater resources tend to prefer private solutions. This condition can increase inequality and reduce cooperation.
Amanda further emphasized that the study highlights the complex relationship between beliefs about merit (success based on effort), fairness, and cooperation.
“Understanding these behavioral dynamics can help policymakers design institutions and policies that encourage collective action and promote more equitable contributions to public goods provision,” she added.
Muhammad Ryan Sanjaya noted that FEB UGM’s involvement in the research was facilitated through the Laboratory of Experimental Economics FEB UGM (GAMA EXEL), which hosted the study in Indonesia in 2023. The research was funded by FEB UGM research grants and the German Research Foundation (DFG).
“The Indonesian data analysis aligns with findings from other countries, showing that many participants prefer private solutions over public ones. However, this does not necessarily imply worse average welfare inequality among Indonesian participants than in other countries, even though their overall welfare levels are lower than the global average. It presents an opportunity for further research,” Ryan explained.
Another finding indicates that cultural factors also influence individual behavior. Countries that emphasize harmony with nature, such as Italy and Germany, tend to invest more in public solutions rather than private ones.
One of the authors, Professor Thomas Hills from the University of Warwick, added that private solutions can serve as a form of protection for those who can afford them but may weaken the provision of public goods.
“This makes public services more expensive for everyone and entirely unaffordable for the poor. The optimistic takeaway is that we can actually do better by investing more frequently and more quickly in public solutions. As a result, the appeal of private solutions will diminish,” Thomas explained.
The publication “The Private Solution Trap in Collective Action Problems Across 34 Nations” is available for free at www.pnas.org/doi/10.1073/pnas.2504632123.
Reported by: Shofi Hawa Anjani
Editor: Kurnia Ekaptiningrum
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