Solutions_ipd.txt

EXERCISE 1

# Compute an ecological competition with All_C, All_D, Periodic("CDD") and Periodic("CCD")

All_C = Periodic("C","All_C")
All_D = Periodic("D","All_D")
eco = Ecological(g, [All_C, All_D, Periodic('CDD'), Periodic("CCD")])
eco.run()
print("Evolution of the population")
eco.drawPlot()
print("History of the population")
print(eco.historic)
print("Evolution of cooperations")
eco.drawCooperations()

------------------------------------------------

EXERCISE 2

# Compute an ecological competition with 5 strategies : All_C, All_D, Tft et Periodic("CCD")

# IN THIS EXPERIENCE, All_D WINS THE TOURNAMENT, BUT IT IS TFT THAT WINS THE ECOLOGICAL COMPETITION!
# Note the evolution of cooperation : it reaches 100%

eco = Ecological(g, [Periodic('C',"All_C"),Periodic('D',"All_D"),Periodic('CCD'),Tft()])
eco.run()
plt.figure(figsize=(10,8))    # pour définir la taille de la figure
eco.drawPlot()
eco.drawCooperations()




----------------------------------

EXERCISE 3

# Encode SoftMajority which plays what its opponent played in majority. In the event of a tie, it shall play Cooperate

class SoftMajority(Strategy):
    def __init__(self):
        super().__init__()
        self.name = "softmajo"
        self.nbCooperations = 0
        self.nbTrahisons = 0
        
    def getAction(self,tick):
        if (self.nbCooperations >= self.nbTrahisons):
            return 'C'
        else :
            return 'D'

    def clone(self):
        return SoftMajority()

    def update(self,my,his):
        if (his == 'C'):
            self.nbCooperations += 1
        elif (his == 'D'):
            self.nbTrahisons += 1
            
# Encode HardMajority which plays what its opponent played in majority. In the event of a tie, it shall Defect
            
class HardMajority(Strategy):
    def __init__(self):
        super().__init__()
        self.name = "hardmajo"
        self.nbCooperations = 0
        self.nbTrahisons = 0
        
    def getAction(self,tick):
        if (self.nbCooperations > self.nbTrahisons):
            return 'C'
        else :
            return 'D'

    def clone(self):
        return HardMajority()

    def update(self,my,his):
        if (his == 'C'):
            self.nbCooperations += 1
        elif (his == 'D'):
            self.nbTrahisons += 1
            
# Encode Gradual. Gradual cooperates on the first move, then if the opponent has just betrayed her 
# for the nth time, enters a period of retaliation (successive Defect) of n rounds followed by 2 
# cooperation moves 

class Gradual(Strategy):
    def __init__(self):
        super().__init__()
        self.name = "gradual"
        self.nbTrahisons = 0
        self.punish = 0
        self.calm = 0
    def getAction(self,tick):
        if (tick==0) : return 'C'
        if self.punish > 0 :
            self.punish-=1
            return 'D'
        if self.calm > 0 :
            self.calm-=1
            return 'C'
        if self.hisLast=='D' : 
            self.punish=self.nbTrahisons - 1
            self.calm=2
            return 'D'
        else: return 'C'

    def clone(self):
        return Gradual()

    def update(self,my,his):
        self.hisLast=his
        if (his == 'D'):
            self.nbTrahisons += 1
  
print("All is ok")


----------------------------------

Exercice 4

# Small equivalence test: Make two tournaments with All_C, All_D, Tft, Spiteful, 
# Periodic('CD') and Periodic('DC').
# The first one using Periodics, Tft() and Spiteful() classes
# The second one using only Mem(x,y,"",name) to code them.
# Check the equivalence by printing the tournament matrix

bag1 = [Periodic('C'),Periodic('D'),Tft(),Spiteful(),Periodic('CD'),Periodic('DC')]
t1=Tournament(g,bag1,100)
t1.run()
print(t1.matrix)
print()

bag2 = [Mem(0,0,'C','allc'),Mem(0,0,'D','alld'),Mem(0,1,'cCD','tft'),
        Mem(1,1,'cCDDD','spiteful'),Mem(1,0,'cDC','percd'),Mem(1,0,'dDC','perdc')]
t2=Tournament(g,bag2,100)
t2.run()
print(t2.matrix)

----------------------------------

Exercice 5

# What is the common name of the strategy that wins the Mem(1,1) ?



----------------------------------

Exercice 6

# Study the phenomena of invasion
# In particular, measure empirically (by few tests) the number of ALL_D required 
# to invade a family of 100 ALL_C in an ecological competition.



----------------------------------

Exercice 7

# Master-Slave Strategies
# It is said that there is a set of Master-Slave strategies if a Master strategy tries to recognize 
# his Slaves on a starter, to better exploit them afterwards.
# Develop a Master strategy that plays TFT unless the opponent has played consecutively 1 time C, 
# 50 times D, 1 time C in which case she always plays D
# Develop a Slave strategy that plays 1 time C, 50 times D, then always C
# Each additional slave brings an advantage to Master!
# Add these strategies to the mem(1,1) competition by putting enough Escaves for the Master to 
# win this competition