The Production Possibility Frontier Game
This game was created for the Foundation Economics programme at Swansea University. The game introduces students to the concepts of opportunity cost, diminishing marginal opportunity costs and production possibility frontier curves. In line with current foundation economics textbooks, production possibility frontier curves and opportunity costs are some of the first economic concepts our foundation students deal with on the course (note). This game involves students playing a production game and creating their own PPF curves. It uses ideas developed from two sources: Mary Hedges’ Tennis Balls in Economics and Bergstrom and Miller’s 1997 book Experiments with Economic Principles.
Running the Game
Our imaginary economy produces two goods – food (tennis balls) & clothing (paper balls). There are 10 workers in total. (The number of workers can depend on the size of your group and the size of your teaching area.)
The two sets of balls are placed into separate raw material containers in the middle of the room. Two empty containers (for finished goods) are placed at each end of the room. A unit is produced when a ball is moved from a raw material container to a finished good container. The students must stand in a “production” line and pass the ball along the line. Each student must hold every ball but can only hold one ball at a time. The containers need to be a fair distance apart. Try to ensure that when all the students are on one side they can only just reach to pass the balls to each other. It is advisable, for health and safety reasons, to have a ‘no throwing’ and ‘no running’ rule.
Production takes place in sessions. Each session consists of 30 seconds of production time. The number of workers producing each good will vary for each session. Start with all the students producing one of the goods;then gradually move students across to the other production line. The number of balls in each end container is your output. Once a session is over, return all the balls to their original containers. Plot the output from each session to create your PPF curve. You can also use your results to calculate the marginal opportunity cost of each good.
The game can be used to demonstrate movement in the PPF curve. For instance, mimic a new production process by allowing students to hold two balls at once. Run this game for the same number of sessions and plot the results against your original PPF curve. This should have the effect of shifting the PPF curve outwards. Alternatively, allow this new production method for only one type of production, which causes the PPF curve to pivot. If numbers allow, you could also increase the number of workers and see what happens to the PPF.
Due to foundation students’ mixed grasp of English, the simplicity of the game is particularly helpful. It enables students to become actively involved in the learning process and constitutes an invaluable supplement to more conventional teaching methods. As the PPF lectures are held at the start of the module, the game also works as an excellent ice-breaker. In order to make the game easier to run, and to offer a visual indicator for the students, I have developed an excel application which can be used [along the way] to display the results of the game. Students thus learn how the PPF if formed, and particularly how it can pivot and shift. Although this application is primarily used to display results in a lecture setting, it can also be emailed to students to give them a chance to play with PPFs and calculate the marginal opportunity cost in their own time.
Bergstrom, T. and Miller, J. H. (1997), ‘Experiments with Economic Principles: Microeconomics’, McGraw-Hill Companies
Dobson, S. and Palfreman, S. (1999), ‘Introduction to Economics’, Oxford University Press
Gillespie, A. (2007), ‘Foundations of Economics’, Oxford University Press
Hedges, M. (2004), "Tennis Balls in Economics", Economics Network
Mr James Mackley
School of Business and Economics
(1) Both the core textbooks we use begin with a discussion of these issues. Gillespie (2007) and Dobson and Palfreman (1999).