Common
Pool Resource (CPR) Simulation
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In the following simulation you
will be a rancher operating your own ranch on the common.
You will decide whether to buy, sell, or breed cows.
The object of the game is to be the wealthiest rancher on the
common as determined by the combination of the value of your cows and the
amount of cash you have. The
winners on each common get bonus points applied to their class
participation grades. |
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The game begins with each
rancher owning 4 cows worth $20 each.
You also have $200 that can be used to purchase cows and you can
accumulate money by selling your cows.
Each rancher makes their own decisions to buy, sell, or breed cows
(every two cows yields one “new” cow).
The value of each new cow you own is either: 1) its purchase price
(if you bought it); or if it is the result of breeding, the “new”
cow’s value is determined by the auctioneer.
This is the current value of all cows divided by the total number
of cows on the common (round to the nearest dollar). |
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It is important for each
rancher to keep track of the unique value of each cow as the game
progresses. Worksheets
are provided to assist you. For example, you may purchase
a cow for $24. That is the
cow’s value until it is sold or the carrying capacity is surpassed.
It is important to keep track of this information in order to
determine the value of your herd. After
each round of buying and selling you will need to tell the auctioneer how
many cows you have and what the total value of the cows are in order to
determine the value of a “new” cow.
You may wish to use the attached
worksheet to keep track of each cow’s value. |
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The common
has a fixed carrying capacity of 40 cows.
Once you have passed the common’s carrying capacity, every
cow’s value will be reduced. When
the 41st cow is reached, each cow’s value should be reduced
by $1. When the 51st
cow is reached, the value of each cow will be reduced by $2.
This continues in the manner specified below:
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#
of Cows
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1
- 40
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41
- 50
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51
- 60
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61
- 70
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71
- 80
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81+
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Reduction
in $
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0
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$1
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$2
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$5
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$10
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$20
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In other
words, if you had a cow valued at $24, its value would be reduced to $23
when the common’s carrying capacity of 40 cows is exceeded. |
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Each
round progresses in two stages:
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1) Each rancher has an
opportunity to buy and sell cows. If
you buy a cow, each rancher must keep track of what the cow costs – this
is the cow’s value. If you
sell a cow, you add the amount to your cash on hand.
At the end of the round of buying and selling, each rancher reports
their total number of cows and the total value of the cows to the
auctioneer.
The
auctioneer then determines the value of a “new” cow.
This is the current value of all cows divided by the total number
of cows on the common (round to the nearest dollar).
The auctioneer will inform you as to what each “new” cow will
be valued. |
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2) Each
rancher then has the opportunity to breed “new” cows.
Every two cows can generate one “new” cow.
Each rancher should then inform the auctioneer how many cows they
now own after the breeding cycle and how much their cows are now worth in
the aggregate.
If it becomes
necessary, the auctioneer will order the ranchers to subtract $ from the
value of each cow they own when the carrying capacity is exceeded.
Ranchers should then report the new value of their cows in the
aggregate to the auctioneer before proceeding.
This
completes round 1. A new
round of buying, selling, and breeding then begins.
You should proceed to repeat steps 1 and 2 until approximately
3:40. |
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End of the
Simulation:
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At the end of
class, each auctioneer must submit the following information to the
instructor:
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The spreadsheet with the
information from each group of ranchers |
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The total number of cows on
your group’s commons |
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Going price for a cow at
the game’s end (i.e., value of a new cow) |
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Gross worth of all farmers
as an aggregate on the common (value of cows + value of money) |
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Average (net) worth of the
ranchers |
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Who is the richest rancher
along with the value of cows and cash |
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Briefly explain what means,
if any, ranchers took to protect the commons |
Each rancher
should write this information down as it may be useful for the memo
assignment. |
