Public Goods Examples and Experiments | MobLab Modules
Follow us

New! Public Goods Module Debuts in Online Assignments

Patrick Burke
In economics, a public good refers to a good or service that is available to all members in a society. Typically, these services are administered by governments and paid for collectively through taxation - such as law enforcement & drinking water.

There are several criteria that differentiate a public good from other goods. These two criteria are:

  • Non-Excludable: the good is available to all members of society
  • Non-Rival: one person’s use of the good does not decrease another’s possible use of the good
The opposite of a public good is a private good, which is both excludable and rivalrous.

One challenge of public goods are that they are susceptible to what is called the Free Rider problem, when individuals benefit without contributing. The concepts of the public good, the Free Rider problem, and tradeoff of private versus societal benefits are widely covered in microeconomics, public policy courses, game theory, and environmental economics. Although students may not be fully aware of public goods as a topic in economics, they use public goods in their everyday lives.

To bring this concept to light, we wanted to develop an online lesson module on this topic to help instructors bridge the gap between real-life public goods examples and textbook readings. Therefore, we are excited to share with you the release of the new Public Goods Online Assignment. This new Online Assignment incorporates videos, interactive games and assessment surveys surrounding MobLab’s Public Good: Linear & Public Good: Discrete (Threshold) games!

In these public goods experiments, your community has started an initiative for a new water purification project to fix recent contamination issues in the water supply. Each member of your community (students) will have the opportunity to voluntarily decide how much to contribute to this project, which will benefit everybody! Water purification projects such as this are a classic example of a public good. Since contributions for the water purification project are voluntary, many members of the community may opt to not contribute as they will still realize the benefits. This may ultimately lead to a market failure, and a contaminated water supply!

Student Game Interface

What is in this Online Assignment?

Our new Public Goods Online Assignment includes an instructional video on how to play the public goods games, followed by some assessment questions. Students are then placed into 5 rounds of the Public Good: Linear game, along with a quick debrief survey on the fundamental of public goods. Once your students have played the first five rounds, they will once again play this game for another 5 rounds, but with a small twist. This time the students’ contribution will have to pass certain threshold in order to gain the benefit of the project. This second game is our Public Good: Discrete (Threshold) game. After students have played this, they are taken to a concept review and through some key takeaways from the lesson.

Instant Results

Sample Results

With this Online Assignment, you will see evidence of free riding. In particular, while you may see reasonably high round-one contributions, contributions will decay relatively rapidly across rounds.

Sample results are above. The box-and-whiskers chart on the left summarizes contributions at the individual level, showing for each round the inter-quartile range of contributions (the box) as well as the minimum and maximum contribution (the whiskers). In addition, the mean is indicated with a red marker and the median with a white line within the box. The chart on the right summarizes contributions by round at the group level.

Instructors have found it useful to save the results images in preparation for the next in-person lecture, or recorded lecture for hybrid/online teaching formats. This provides you with the opportunity to gauge them on their observations during gameplay. How did your contributions change from round 1 to round 5? Were there free riders present in your group? Were YOU a free rider? What policy measures can be take mitigate this market failure? Using these public goods games as an engine for in-class discussions can get your students engaged and thinking like economists!

This Online Assignment demonstrates how the market fails when confronting the case of public goods. Students will experience the urge to free ride when deciding whether to contribute to the public goods. Will the contamination issues be fixed?

Thank you for reading! We hope you enjoy this assignment with your students. Whether you’re teaching in person, online, or both, MobLab has got you covered with Online Assignments for asynchronous learning. Would you like to learn more about MobLab’s assignments? Get in touch with our team. Schedule a meeting with someone from our team to get started!