1. Common Pool Resource Game: Linear Withdrawals Mechanism
Student Instructions

2. Decision Screen You are placed into a group of size 4.
Each group starts out with 40 tokens.
You decide how many tokens to withdraw (maximum 10) from the group to keep as “My Tokens” and how many to leave “Tokens Left”
The highlighted column shows your possible earnings based on the decisions of others in the group (scroll to see more).
This is based on the following parameter settings on the server iPad:
Time Limit: 3 Government Provision Point: 0
Size of each group: 4 Federal Government Provision: Off
Force Group Size: On Voluntary Provision Point/Matching Point: 0
Token Endowment: 10 VCM Multiplier: 2
Token Giveback: 1 Matching VCM Multiplier: Not functional in the current version
Note: The labels are designed for the isomorphic public goods game.

3. Decision Screen
To move the tokens to the “My Tokens” box finger drag each token to the left until you are satisfied with your decision.
You can move tokens back and forth until you lock in your decision.
Press and hold the “Done” token to lock in your decision.

4. WHAT IF? Analysis Touch the others’ average row to highlight.
The red box is your round earnings IF you keep your current decision (5) AND IF the others’ group members leave the average expected (7).

5. Summary Screen After all decisions you see the Others’ Average left.
The Total Group Tokens are the sum of tokens left by the group which are multiplied by 2 to get the Total Value.
The Total Value is split evenly to get your equal share, which is added to your tokens kept = My Earnings.

6. Discussion of the rounds
Who left all of their tokens each round? Why?
Who withdrew the maximum tokens each round? Why?
Who did something else?
Did verbal communication help more?
Is this more of a coordination problem or a cooperation problem?

7. Common Pool Resource Problem
Private goods: excludable & rival
Common Pool Resources: nonexcludable & rival
Incentive to overextract – cannot exclude others from extracting, the cost of their extraction is shared by everyone
Conditional Cooperation – cannot expect others to extract less, so you extract before the resource is gone
Combined effects result in overextraction