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Week 10 - Prisoner's dilemma

pbrodfue's picture
Describe what happened when you played prisoner's dilemma. Give an example of a prisoner's dilemma operating in your life.
aybala50's picture

Competition

When I played the prisoners dilemma I started out competing every turn and I won. Then I got curious as to what would happen if I started cooperating and I won again. Then I started mixing it up and still kept winning. At this point I was getting bored as I didn't realize a pattern because no matter what I did I kept winning! After reading some of the postings I realize that I missed the meaning of Prisoner's Dilemma completely. The reading for today was also very helpful. If I chose to compete, the computer would compete with me the next turn. It would copy my move the next turn, so if I compete the whole time I win. If I cooperate the whole time I should end evenly with the computer and if I mix it up, that's when there's a chance I could possibly lose. 

 An example of a Prisoner's Dilemma in my life? I'm not exactly sure as I can't really think of a clear one. The obvious one that pops into my head is the competition amongst the students, especially in one's major department. I would love to be the best student in the psychology department, but at the same time I need the other psychology major's around me. If we help each other there's a better chance we will grow in our field, but at the same time there's always a competition to be the best. So, is it more important that I compete with them and stand alone, or is it better for me to cooperate and all of us growing together?  

xhan's picture

When I first played this

When I first played this game, I decided to “cooperate”, since I didn’t want to “beat” the game, I just wanted to be able to understand how to play the game. As time went on however, I realized that no matter how badly I played, I would still win. At that point, I unconsciously started to try to “outsmart” the game by trying new techniques and tried to play offense rather than defensive. My behavior in this game reminds me of how I would play soccer: rather than actively try to obtain the ball from my opponents and try to get it into the goal, I would remain passive aggressive, and only try to get the ball from the opposing team if the ball was on my side of the field. I would also try to pass the ball to other members on my team, rather than to shoot the ball into the goal. Even though attempting to shoot the ball into the goal is riskier than passing it to other members on the team, it is also more rewarding, say if I did happen to make a goal. In terms of Prisoners Dilemma, even though it is difficult to think out of the “norm”, instead of letting the game influence my actions, it is both exciting and challenging to think of ways to go beyond  the limits of the game in overcoming it.

lwscott's picture

Player's Dilemma

After I finished playing it took me a few minutes to figure out why it was called Prisoner's Dilemma. Finally, I realized that the scenario is that Serendip and I are both prisoners being interrogated (or something like that,) and I can rat Serendip out by competing or I can chose to cooperate. If Serendip and I both cooperate then neither of us would rat the other out (about whatever crime we committed). If we both compete, and blame the other person, the interrogators will know that we're lying. If one of us competes and the other cooperates, the on that cooperates will get in trouble.

I find that I play a Prisoner's Dilemma type game when I play soccer. I can choose to take the ball myself and soccer (and risk losing the ball) or I can cooperate with my teammates and get an assist. It may be selfish of me to take the ball myself but if I don't trust my teammate, and I'm afraid they might lose the ball, I feel like I have no other choice. There is always a chance that I choose to "compete," choose not to pass, and lose the ball, (aka my teammate also chooses to compete). In soccer, you always have to consider what your teammates will. When I was playing the Prisoner's Dilemma I kept trying to guess Serendip's next move. In the end it's a matter of chance. Serendip has a 50% of choosing compete and a 50% chance of choosing cooperate.

lwscott's picture

Player's Dilemma

After I finished playing it took me a few minutes to figure out why it was called Prisoner's Dilemma. Finally, I realized that the scenario is that Serendip and I are both prisoners being interrogated (or something like that,) and I can rat Serendip out by competing or I can chose to cooperate. If Serendip and I both cooperate then neither of us would rat the other out (about whatever crime we committed). If we both compete, and blame the other person, the interrogators will know that we're lying. If one of us competes and the other cooperates, the on that cooperates will get in trouble.

I find that I play a Prisoner's Dilemma type game when I play soccer. I can choose to take the ball myself and soccer (and risk losing the ball) or I can cooperate with my teammates and get an assist. It may be selfish of me to take the ball myself but if I don't trust my teammate, and I'm afraid they might lose the ball, I feel like I have no other choice. There is always a chance that I choose to "compete," choose not to pass, and lose the ball, (aka my teammate also chooses to compete). In soccer, you always have to consider what your teammates will. When I was playing the Prisoner's Dilemma I kept trying to guess Serendip's next move. In the end it's a matter of chance. Serendip has a 50% of choosing compete and a 50% chance of choosing cooperate.

lwscott's picture

Player's Dilemma

After I finished playing it took me a few minutes to figure out why it was called Prisoner's Dilemma. Finally, I realized that the scenario is that Serendip and I are both prisoners being interrogated (or something like that,) and I can rat Serendip out by competing or I can chose to cooperate. If Serendip and I both cooperate then neither of us would rat the other out (about whatever crime we committed). If we both compete, and blame the other person, the interrogators will know that we're lying. If one of us competes and the other cooperates, the on that cooperates will get in trouble.

I find that I play a Prisoner's Dilemma type game when I play soccer. I can choose to take the ball myself and soccer (and risk losing the ball) or I can cooperate with my teammates and get an assist. It may be selfish of me to take the ball myself but if I don't trust my teammate, and I'm afraid they might lose the ball, I feel like I have no other choice. There is always a chance that I choose to "compete," choose not to pass, and lose the ball, (aka my teammate also chooses to compete). In soccer, you always have to consider what your teammates will. When I was playing the Prisoner's Dilemma I kept trying to guess Serendip's next move. In the end it's a matter of chance. Serendip has a 50% of choosing compete and a 50% chance of choosing cooperate.

lwacker's picture

Do I beat the system... or play well with others?

While participating in the "Prisoner's Dilemma" game I found myself cooperating with Serendip for my first six turns. It was not until the seventh turn that I decided to compete with Serendip. However, if I were to compete for a turn the very next turn Serendip would do the opposite and vice versa. I ended up winning the game, with more gold coins in my possession, at the ends of twelve rounds but I think it was only because I had been the first participant to choose "compete" as an option. In class on Tuesday we discussed the real world application of the Prisoner's Dilemma to our lives and how we have been directly impacted by winning or losing the game. With a big test coming up in GEO on friday, and an invitation to a group study session from my GEO peers, I have realized that the choice to cooperate together, though often times as risky as the choice to compete, is ultimately the most productive and kind-hearted way of going about decision making. 
mmg's picture

Instinct

My natural instinct was to compete. For some reason, the prospect of "serendip already choosing his move" and a fiendish cyberspace wizard "watching" over me put me into combat mode. I tied with serendip six  few times, lost twice, and won twice. The game, I felt just kept sucking me in, and to begin with I really wanted to win, just to prove the my human brain can come up with a way to destroy something created by another brain physiologically similar to mine. Soon though I realised the apparent foolishness in my desire. This game was just as random as anything could get. It is about probability. There is a 1/3 chance you will win, a 1/3 chance you both will 'half-win' and a 1/3 chance neither of you will every time you play. For some reason this reminded me of my genetics class last year. When there is a cross between two dominant heterozygous alleles for a particular trait, there is a 1/4 chance of getting each genotype possible with the combination. Say the traits are a cross between Aa and Aa, we get AA, Aa, aA and aa. Yet, Aa and aA are essentially the same - the co-operation of the two kinds of alleles. The prisoner's dilemma to me is pretty much genetic inheritance.

 

Last year, when I was in boarding school, my room mate and I got into a 'fight' which involved us not to speaking to one another for five days. (We happen to be best friends, so that was hard). Both of us refused to initiate any sort of ceasefire. We cleaned our rooms every Sunday, and being that we were still in school, our dorm parent came in to check in on our rooms then. My 'prisoner's dilemma' involved around whether I should clean my room on my own or not clean it at all. There was a possibility that my room mate would clean it eventually, but she might not too, seeing as I hadn't cleaned it either. Given that we were in war, I did not want to wave any sort of white flag and do her part of the cleaning! Yet, if neither of us cleaned the room, it wouldn't go down too well with my dorm parent, to say the least. I ended up cleaning half of the room and noticed that my room mate did the other half. Even in war, we 'co-operated'. No, we did not start speaking soon after that.

 

swhitt's picture

...

Like several of you, I found that serendip would mimic my last move.  I didn't play particularly systematically, though.  I usually won if I cooperated for several moves and then competed once or twice before reestablishing a pattern of cooperation (lulling serendip into a false sense of security ;) 

I also am not sure how to apply the game to real life.  All this talk of cooperation v. competition makes me think of communism v. capitalism - the former of which works in theory only, the latter of which can be unpalatable, but functional.  Individually, I tend to favor competition over cooperation - I think when people are in competition they try harder and do more interesting things. I don't advocate a cutthroat approach, though.  To me, all of this discussion is contained under the assumption that the players agree and adhere to the terms of the fight (that there is an expectation of fairness).  In which case, as with all interaction, the foundation is one of cooperation (we cooperate in agreeing to play).  Without this, all bets are off. 

yhongo's picture

Prisoner's Dilemma

When asked to choose between "cooperate" and "compete", I went with "cooperate" because like Katie and Michelle, I am more of a cooperating person rather than a competing person. I kept on clicking cooperate and resulted in having the same score as Serendip. From this game, I concluded that it is certainly beneficial for both players by cooperating. Cooperation, after all is a mutually balanced relationship where both players put in the same effort in order to get the best possible outcome. 

A real life example would be a group project in which students are graded based on the overall project rather than individual effort. In other words, everyone in the group receives the same grade, so everyone has to put in some effort so that they would receive a good grade for the project. 

jpfeiffer's picture

Prisoner's Dilemma

By nature, I would say that I would rather cooperate than compete. However, after I cooperated several times with the computer, I felt it was a bit redundant, so my next move was to compete. Originally, when I first began to compete, it was to my advantage, however, as I continued to compete, the number of coins between me and the computer began to decrease, and my advantage soon discipated. In another sense, I guess you could say that the more that I competed, the more that I was punished. I personally was not a fan of the game, and like we discussed in class, I feel as though it was really predictable after a while and it would be more interesting for there to be more variation.

A time in my life that reminded me of the Prisoner's Dilemma, would probabaly be each time I play golf. Most of the time, in golf, I rather take the risk ( compete) than cooperate with the golf course. For example, challenge a water hazard or an out of bounds marking. I think it is more rewarding in a sport, and probably most aspects of life, to compete and receive the benefits than to cooperate and possibly miss out on opportunities.

Marisa La Piana 's picture

Prisoner's Dillemma

The first round I tried to cooperate, so we tied. Then I tried competing and I beat serendip by 5 points. In an economic sense, cooperation leads to equality but doesn't encourage the improvement of merchandize wheras competition fostoring innovation and improvement but leads to monopolies and an unequal distribution of capital. In a social sense, cooperation can lead to synergy, where both people bet more out of a given situation wheras competition can fostor animosity and lead to severed ties. Personally, cooperation can lead to a win-win situation wheras in competition someone ineviably has to lose. A United States without competition would be completely unsuccessful because entreprenuership and innovation wouldn't exist. If we all cooperated we would have equality, which means we wouldn't have a social hierarchy. Therefore,people would avoid doing the "dirty work" of the society and it would collapse. Competition works because it plays into human nature. History has shown us that a socialistic "cooperative" society only works when it is small scale and everyone is truely dedicated to pitching in for the good of the group. This is difficult to accomplish.

nmackow's picture

cooperate.

The first time I played the game, I cooperated the entire way through. I wanted to see if the computer would vary its moves. But alas, no. I do believe this took some of the mystery out of the game, the knowledge that the computer's move was whatever I last did. I tried a variety of moves, alternating between 'compete' and 'cooperate'. In the end I could only manage to have at most 5 coins more than the computer. I never lost.I didn't really see the purpose of the game. I suppose that if this were reality, I would generally chose to cooperate. If this could relate to matters of business and money, I think it would be best to work with a competing business to attain mutual satisfaction, rather than to risk working against them.
Shoshi's picture

Compete?

I found competing to be best because I gained more gold than Serendip by the end of the game. Cooperating got me very little in the way of monetary gain, whereas with competing I always got lots of coin no matter what Serendip did. 
hwiencek's picture

prisoner's dilemma

I played the game twice and tied with the computer both times.  The first time I cooperated for each turn and the game ended in 10 rounds.  The second time I cooperated a majority of the time, but competed 7 (out of 17) times.  Each time I competed the computer copied me the next turn.  

I have to admit, like others, I don't really get the point of this game.  In fact, I'm wondering if I maybe just don't understand it completely.  I suppose I understand it if I was playing against a real person or if I were observing many people playing the game--in both cases I might be able to learn something about what people are likely to do.  However, playing against a computer seemed rather pointless to me.  I'm also not sure what we were supposed to learn from it...

  I guess I would classify all of my relationships with people as Prisoner's Dilemmas.  The ideal relationship for me is win-win...I am able to help the other person and they are able to help me--mutualistic.  However, sometimes relationships may need to be in the lose-win or win-lose phase for a period of time...as long as the end result is win-win.  For example, sometimes you need to give more to another person and not receive anything in return for the time being if the other person is in pain, etc.  And the reverse is also true.  I think that the best example I have of this in my life is my relationships with my best friend, Alison (and probably to some extent my mother, but I think I probably rely more on her than she does on me).  In these relationships there is a feeling of unconditional love and support.  We are there for each other no matter what.  Some days all I do is complain and she will help me through (win-lose).  Others it is the opposite (lose-win).  But in the end, just knowing we each have that support system makes it a win-win situation.  (Also, I would argue that being able to support and help someone you care about could also be a win because it makes you feel good...)

Yellow's picture

Prisoner's Dilemma

I have played this game before, but in my economics class in high school, with other people (anonymously), and with consequence--EXTRA CREDIT POINTS. Unfortunately, while I chose to cooperate and accept the points my opponent offered, he ended up with 4 extra credit points and I only got 2. And my grade in the class needed the extra credit more. Playing the game in econ was to demonstrate the game theory.

But, since I knew how to play the game, I won against Serendip in 2 of the 3 games I played against it.  And the time I lost, it was only by 3 or 4 points. However, I like playing prisoner's dilemma with actual repercussions: for instance, imagining you are in jail and your accomplice can blame you, and you get jail time and they get off free, or you can blame them while they blame you and you both get jail time, or both of you can keep evidence hidden and get lessened jail sentences.

mkmerrill's picture

dilemma

I missed the point of the game. As we talked about in class it was too easy to figure out serendips next move; if you cooperate it will, but if you compete it will compete in the next round. I started off cooperating every time, and I won every time. Then after figuring out the pattern it became just as easy to win. To me it reminds me of high school. So many kids competed with the teacher by not doing homework when it was due or at all. I guess you could say that those students who did well in the class figured out the "pattern" and found that by turning in homework you get the credit which ultimately benefits you. The same can be said of alot of everyday tasks. If you figure out the pattern; what works and what doesn't, then you can make your next move accordingly.
akaltwasse's picture

"You told me it was a game!"

Well, I guess I'm a competetive person, because that was my first move.  BUt it's a game, right, so don't you want to win?  That's probably why I missed out on the real-life application of the prisoner's dilemma, because i took it as a game.  Eventually I switched from competing to cooperating and still won, but I was only able to win if I began by competing.  I'm not exactly sure what lesson that's supposed to be.  I agree with Elizabeth's complaint that Serendip's moves were not random and instead copied your last move.  Of course win-win situations (cooperating) are the best in life, assuming you don't look at it as a game.  If the prisoner's dilemma had random moves, then maybe the message that cooperation is better would get across more easily, if that is in fact the message.
akaltwasse's picture

"You told me it was a game!"

Well, I guess I'm a competetive person, because that was my first move.  BUt it's a game, right, so don't you want to win?  That's probably why I missed out on the real-life application of the prisoner's dilemma, because i took it as a game.  Eventually I switched from competing to cooperating and still won, but I was only able to win if I began by competing.  I'm not exactly sure what lesson that's supposed to be.  I agree with Elizabeth's complaint that Serendip's moves were not random and instead copied your last move.  Of course win-win situations (cooperating) are the best in life, assuming you don't look at it as a game.  If the prisoner's dilemma had random moves, then maybe the message that cooperation is better would get across more easily, if that is in fact the message.
eolecki's picture

Economic Incentives

In my economics class we looked at a fairly similar example to prisoners dilemma.  Two business that could either choose to produce at high production or low production.  If they both did low both companies got a profit of 300, if they both did high they got a profit of 30, and if one did high and one did low the one that did high got 400 and the low got 10.   So, people have been saying that they are cooperative in real life and would rather know that they were being cooperative than competing.  In economics the main idea is that people respond to incentives.  Would you rather have $400, $300, $30, or $10?  Well of course you want $400.  From this situation, economic theory says both firms will produce high and only get $30.  Why? because both firms have an incentive to produce at high levels.  If both firms have one chance to make money both are going to try and make a higher profit because to matter what the other one chooses they will have a better chance off high production.  If one firm produces high and the other produces low the first gets $400 instead of $300 and if the other firm produces high then they get $30 instead of $10.  So clearly the best economic decision is always to compete.  However, there is an exception if there is going to be repeated interaction and the firms can work together to both get high profits ($300) at low production.  But this agreement has to include punishment for firms that cheat the system. 

I played the game differently than a lot of people because I was viewing it in terms of economic incentives rather than with the principle of cooperation or competition. 

Anne Dalke's picture

Zero-Sum Grading?

cooperated 3 times:
33 me/33 serendip
33 me/33 serendip
66 me/66 serendip

competed 3 times:
14 me/9 serendip
14 me/9 serendip
14 me/9 serendip

cooperated, then competed,
alternately, 3 times:
33 me/28 serendip
28 me/28 serendip
28 me/23 serendip

competed, then cooperated,
alternately, 3 times:
30 me/25 serendip
25 me/25 serendip
35 me/35 serendip

so...my data accords w/ what abhattacha said so clearly above:
BEST TO COOPERATE - WIN-WIN SITUATION + PEACE OF MIND

I'm trying to think about what win-win situations I have been in. In the terms of this game, I'd say that Peter and I have actually been trying to create a win-win situation in this class. Do you think that is possible? Can thinking out loud/reading/writing papers be a zero-sum game? If we all cooperate? When there's grading @ semester's end?

mcchen's picture

Playing Prisoner's Dilemma

The first time I played the game, I clicked randomly and by chance I had won but barely.  The second time, I chose to compete with serendip more times than I cooperated.  I guess I was trying to find a pattern in serendip's choices when it was probably trying to do the same with my choices.  That time I played it, it said I was borderline on the number of coins I had to have throughout the whole game.  So I played the game one last time and "won" although I'm not quite sure what that really meant.

A prisoner's dilemma in my life would be when we used to play jeopardy in high school for extra credit points.  If we all wagered the same amount of points, we would all get the same amount of points.  But since we did not know how much other groups wagered, we would try to wager the highest amount possible to win because we all wanted to get the most extra credit points possible.

abhattacha's picture

PLAYING PRISONER'S DILEMMA

I. COOPERATING RIGHT THROUGH - 12 rounds

  No.of gold coins - Me 36

                             Serendip 36

  Av. no. of coins  - Me 3.00

                             Serendip 3.00

 

II. COMPETING RIGHT THROUGH - 10 rounds

   No. - me 14

           ser. 9

    Av. - me 1.40

            ser. 0.90

BUT FLIRTING WITH AN INCONCEIVABLY FOUL FATE THE WHOLE TIME

 

III. COOPERATING AND COMPETING ALTERNATELY - 10 rounds

   No. - me 28

           ser. 23

   Av. - me 2.80

           ser. 2.30

 

IV. COMPETING AND COOPERATING ALTERNATELY - 15 rounds

    No. - me 40

            ser. 35

    Av. - me 2.67

            ser. 2.33

 

V. COOP 5 rounds , COMP 5 rounds , COOP 1 round -11 rounds

       No. - both 24

       Av. - both 2.18

 

VI. COMP 5 rounds , COOP 5 rounds - 10 rounds

        No. - both 21

        Av. - both 2.10

 

MORALS -

I. BEST TO COOPERATE - WIN-WIN SITUATION + PEACE OF MIND

II. A CUT-THROAT STRATEGY IS BAD NEWS - MODEST WINS + PLAYING WITH FIRE. 

III. & IV. - MIXING STRATEGIES WORKS WELL , PARTICULARLY IF START OFF COMPETING .

V. & VI. - CHANGING HORSES MID-STREAM NOT AS PROFITABLE .

 

Being part of the two - member School Debate Team taught me the important lesson that a win-win situation always works best .

Working together to prepare  both a strong proposition and opposition gave us wins through the preliminary rounds to the finals of the Inter-School Debating Championships . We learnt from the many strong teams which fell by the wayside even though , very often , one of the team members won the Best Debater Award in that round . 

We reached the finals and won ; and guess what ? Both of us jointly won the Overall Best Debater Award !  

 

 

 

 

 

stephkim's picture

prisoner's dilemma

Although I heard of this experiment before, it was my first time actually playing it.

At first, I clicked cooperate and rarely the other option, but as the game progressed, I saw that I was actually winning money. I then switched over to the compete option and realized that even though serendip was also competing, it didn't matter because I had a significant amount of money: if i clicked compete each time, serendip would either win just 1 coin, or would lose 3 (? i think). It didn't matter if i was also winning 1 because as long as I clicked compete, I would be earning either just 1 coin, or 5.

I was probably fortunate in winning because I had a lead of multiple coins in the beginning of the game.  The first couple choices you make most likely predict that winner because after a while, you realize that it's a win-win situation once you have more than a four coin lead.

stephkim's picture

example

oops I forgot to upload the example:

 

When my sister and I got in trouble together, our parents separated us and gave us a piece of paper each. We were to write down what happened to that they knew that if the stories didn't match, one of us were lying.

My sister and I ended up writing very generally about the situation, so we were let off HAHA.

cantaloupe's picture

Rewards

The first time I played Prisoner's Dilemma I chose randomly and ended up tying with serendip.  That seemed rather boring, but I tried again with the randomness and won.  Sensing that I should probably try a strategy, I decided to hit cooperate every time and so did serendip.  We ended up tying and it was boring.  The next time I hit compete every time and we ended up tying again.  The game got pretty pointless feeling, so I stopped.  However, I decided that I was having the most fun when I was randomly choosing compete or cooperate.  This is because there was an element of suprise.  I wasn't quite sure what serendip's move would be.  Yet, if I chose the same one every time, I became bored.  This directly relates to how I like to live my life: sometimes I like to cooperate, sometimes I like to compete.  I would lose interest in my life if all I did was cooperate with everyone else, but I would become tired if I competed all my life.  For example, I have been practicting karate for eight years and I cooperate with everyone in my dojo to work on technique and help others.  But, it gets tiresome to always work at the pace of the slowest person and work as a group because naturally, everyone works at a different pace.  Once a year, we have a tournament and get to compete.  My really good friend and I compete against each other every year even though we spend all year helping each other with what we compete with.  That competition helps me stay focused on cooperating.
ihe's picture

I played the game three

I played the game three times: once choosing a combination of both compete and coordinate, once choosing only compete, and once choosing only to coordinate. The safest was to coordinate, becuase both of serendip and I had got the same amounts of coins.  By clicking soley on compete, I had won, but I had also played with"Inconceivably Foul Fate."

My real life example of Prisoner's Dilemma would be getting into trouble when i was young. We weren't allowed to chew gum in class, and my teacher caught me and my friend with gum. So we promised each other that neither of us would tell the teacher where we got the gum from. When the teacher spoke to us individually, I had said i didn't know wher ethe gum came from, and she told the teacher that i had given her the gum. got into trouble for that :(

SaraO's picture

Prisoner's Dilemma

I feel I missed the point of the game. I played multiple times but out of having to, I never really got caught up in it. It was my natural instinct to cooperate at first, so for the majority of the first game I cooperated, I tied the computer, and it said that I could do better. When I competed for the whole time, I won, multiple times. Not that it ever really mattered. At the conclusion of the game I was just thinking "so I won, what now?". 

My own prisoner's dilemma (I'm sure I've had more but this is the easiest to remember) was in the 6th grade. A teacher of ours (he turned out to have severe psychological problems) accused me and a few girls from my homeroom of stealing his tax returns. He left varied "evidence" in two girls lockers. We had the choice of going our separate ways and leaving those two girls hanging out to dry, or to band together, and say we were all innocent, because we all happened to be together during the said incident. We stuck together, and we did well. Our principal realized that he was lying, and that he was a bit challenged. He was dismissed from the staff.  

lraphael's picture

to be selfish or to be nice

Honestly, the point of the game somewhat confuses me but the first time I played it I used my competitive instinct -- I competed every time and came out on top. The second time I tried to get about even with serendip, but I competed only ONCE, and yes we came out even anyways. To me it is confusing but it made me think about all of the times I was selfish versus the time I tried to be nice and selfless. I guess when I try to think of a time in life when I did this (this might be a stretch but it is what comes to mind) is my roommate in 9th grade (I went to a boarding school). We never spoke one word to each other the whole year. We were young and not ready to live on our own, so we only thought about our needs and didn't even bother to acknowledge each other's needs. I guess what the game made me think about is that being selfish may make you rise to the top, but you leave others behind. Now at Bryn Mawr, I have learned how to handle living with others.  I talk to my roommates about the tinniest of issues, because I realize at the end of the day it is the better solution to try to balance things out rather than a more selfish situation.

Leigh 

emily's picture

Cooperate is the way to go!

The first time I played prisoner's dilemma, I chose to cooperate every time. The computer also chose to cooperate every single time and we ended up with the same number of coins. I sensed the computer was mimicking my pattern for some reason, so the next time I cooperated every time, as did the computer, except for one turn in the middle where I competed, and in the next turn I cooperated and the Computer competed (so we were even). Then on my last turn, I chose to compete (I knew it was the last turn because of the number of coins I had last time on the last turn). When I chose to compete on the last turn, the Computer chose to cooperate and I won. Although these two trials may have been random, I got a strong feeling that the computer was sensing my pattern and playing accordingly. A real world example of the prisoner's dilemma can be seen in The Tragedy of Commons essay, specifically the section about pollution: "the rational man finds that his share of the cost of the wastes he discharges into the commons is less than the cost of purifying his wastes before releasing them. Since this is true for everyone, we are locked into a system of "fouling our own nest" so long as we behave only as independent, rational, free enterprisers". If every single person chose to cooperate, we would all come out even. But in a way, if we choose to do what is best for our own selves immediately right then, it could be bad for us in the long run. Choosing to be selfish in the Prisoner's Dilemma leaded the computer to retaliate against me, which could have potentially lead to competition and more selfishness and even the potential to lose. But choosing to cooperate seemed to be the best option. 
kscire's picture

Game

Playing the prisoner's dilemma I chose "cooperate" about 5 times and then I quit the game. I had no desire to compete with Serendip, especially over virtual coins. There was no variation in the scoring so I figured no matter what I chose, cooperate or compete, the scores would remain equal. I don't think the prisoner's dilemma has much of a place in my life. At least 9/10 I will always chose to cooperate vs. compete. I would much rather put myself at a disadvantage knowing I am trying to cooperate. Even if I was guaranteed to win by clicking compete I wouldn't. 
msmith07's picture

I guess I'm just a cooperator?

Though I said this in class already, I agree with Katie. I chose to cooperate because in any situation I could think of in my life, that is what my natural and instinctual choice would be -- to cooperate. Even in the *real* prisoner's dilemma, where the prisoners must choose to tell on one another, or to keep quiet, I can't imagine myself not cooperating. It is simply not in my nature. If we're talking about real gold coins, you can keep them; I'm not one to compete for material posessions.

Even in the "real life" example I brought up in class-- where "cooperating" would be sharing class notes with someone and "competing" would be using those notes to benefit one's own grade without assisting the original note-taker-- I have only ever played the role of the cooperator, to my knowledege. Like Katie, I don't think the prisoner's dilemma has much of a place in my life either.