CSC107 - Lab 5
Population and Evolution

Assigned Apr 5th
Due Apr 12th 5 pm

Show your work on all questions for full credit.

References

Question 1

Alter the Wolves, Sheep, Grass simulation so that the reproduction is not based on random probability, but on how much energy the wolves and sheep have. If a sheep has energy over a certain threshold, defined by a new slider, the sheep will reproduce, and similarly for wolves.

Write the changed procedures, and discuss the differences between this new model and the original model.

Similarly, alter the grass reproduction to proceed in a manner similar to forest fires spreading. If a patch is green, then 25% of the time have it find one brown NSEW neighbor and ask this neighbor patch to turn green.

Write the changed procedures, and discuss the differences between this new model and the original model.

Question 2

Find the optimal choice for both player A and B in the following games. Is there an equilibrium point where both players are happy?

B
A3, 42, 3
4, 25, 5

B
A3, 41, 1
0, 21, 2

Question 3

Using the Iterated Prisoner's Dilemma webpage above, calculate the scores for the following competitions:

Question 4

Create a custom strategy of your own, by selecting the values for T, P, R, S and B. Write down your values for this strategy. Calculate your score versus the following strategies:

Question 5

We initialize a population with 12 individuals to play the Prisoner's Dilemma, 4 playing the Tit for Tat strategy, 4 playing Always Defect, and 4 playing Always Cooperate. After the first round of competition with random pairings and 10 games, we find that on average Tit for Tat scored 20 points, Always Defect scored 30 points, and Always Cooperate scored 10 points.

According to the Replicator Dynamics, what should the population look like next iteration?

© Mark Goadrich 2010, Centenary College of Louisiana