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Game Theory and Human Interaction
Monday, February 22nd, 2010 12:51 am
Written by: acirv
“A Case of Game Theory”. On his website, Michael Sympson, discusses game theory as it relates to different aspects of real life. In the second paragraph, Sympson relates Charles Darwin’s theory of natural selection and evolution to a Nash Equilibrium and playing dominant strategies in a game. He states, “…only the ones where the individual player keeps playing the right hand, can survive.” This shows that unless players play strategically and adjust their approach based on the potential payoffs for each strategy, they will essentially be phased out and in the sense of living organisms will die out and become extinct. Sympson also discusses John Mynard Smith’s use of game theory and probability and how it links to the actions people take when working with others. These two topics among others create a connection between the material discussed in class and the different interactions that we face throughout life.
During Sympson’s discussion of different strategies it becomes evident that there is a clear connection with Charles Darwin’s theory of evolution. I think that this idea brings up a very interesting connection between science and the mathematics of game theory. The ideas discussed in class regarding determining a dominant strategy now appears to be relevant to the stability of species. Each decision that an organism makes can change how it continues to evolve as well as if it continues to exist. By choosing a non-dominant strategy, an organism risks making an action that could hurt its future. As Sympson states, “Not playing at all is not an option.” It is under this mind set that it can be assumed that every living organism is in fact always playing a game, whether it be a two person single game or a repeated game. With these repeated games, there is the potential for people to learn from their previous mistakes and hopefully change their strategy in future rounds and have a more successful outcome.
These repeated games also come into play when determining how a person should act and engage with another. Sympson refers to this when he states that, “people usually know that it pays to appear playing nice and being cooperative.” I think this statement has a lot of relevance to game theory in that there are clear advantages to be gained by learning from previous rounds or games and that these advantages can be used by players to better achieve their final goals in life or payoffs.
http://www.michaelsympson.com/morals
http://expertvoices.nsdl.org/cornell-info204/2010/02/22/game-theory-and-human-interaction/
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Game Theory and Best Price for Gas
Sunday, February 21st, 2010 10:53 pm
Written by: aromnomnom
So there you are, on a long drive to somewhere new when suddenly, you realize that you’re gas tank is getting closer and closer to empty. You know that you need to fill up soon, but you want to make sure you don’t get ripped off, so what do you do? Well, according to the blogger over at Mind Your Decisions, there is a way! He simply suggests that you consider finding the cheapest gas much as you would consider finding the perfect mate. In an earlier post he details the best way to find “true love.”
First he points out that “true love” is relative and that the only way to place a value on your relationship with someone is to compare it to a previous one. Keeping this in mind, one formulates a plan. Say for example at max you want to date 3 people in your life. That means for each person you date you have a 1/3 chance of them being the “correct person.” However, if you adopt the strategy that you get to know but always end it with the first person and then settle down with the next person who is better than the first person, you increase your chance of “winning” to 50%. The idea is that the only two ways you can lose is if you date the best person out of the three first, or if you date the worst person first and date the second best person after them. In order to figure out how many people you need to pass by in order to make this strategy most effective involves how many total people you want to date. Applying this basic concept to finding a gas station means that your best response to the first gas station you see is to keep driving along and then pick the next gas station that has the best price. This theory is made stronger because gas stations tend to cluster together due to the concepts of social optimum not always being the Nash equilibrium. If gas stations are equally spread out in relation to consumers, it is the social optimum as ever gas station is equidistant from every consumer, however if one gas station moves they will dominate more of the market by placing themselves closer to some of the other gas station’s customers but still the nearest to their old customers. Since Nash equilibrium means that there’s no incentive for either player to deviate from the current strategy the social equilibrium doesn’t match the Nash equilibrium.
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A Case of Game Theory
The Greek philosopher Heraclit was perhaps the first to realize that conflict is the engine of progress. “Homer,” he says, “was wrong to pray ‘Would that strife might perish among gods and humans!’” because “Homer did not see that he was praying for the disappearance of the Universe." In evolutionary terms, the competition over territory and mating issues is propelling civilization and biology to the next level; the eternal war between predator and prey provides the peregrine with better eyesight and improved maneuverability and the rabbit with better hearing and higher speed. But it would be wrong to think of progress entirely in terms of an all out arms race. Conflict is also creating the need for cooperation and better communication. During the Vietnam War the methods of emergency medicine underwent a revolution. Since then more lives have been saved in the ER units of our hospitals than casualties have died in that war. So here is another truth for you, equally unsuitable for the kiddies in Sunday school: history is not about good versus evil, but smart against stupid, with good and evil sitting on both sides of the conflict. Life is not a contest to pick the nicest kid on the block, nor is it about the survival of the meanest. Instead it is all about to stay alive, keep the game going and not run out of chips, whilst biding time for the right move when we feel our moment has finally come – of course without any guarantee it will ever occur. Yet no matter how relentless the competition, a stabile environment for breeding and nurture is in every player’s interest; renegade individuals trying to take undue advantages disturb the equilibrium and ultimately the existence of the “system,” and there is no “game” without the system sustaining it. Therefore mavericks need to be dealt with, or the species – the “system” – looks extinction in the face. Since there is no such thing as a collective conscience and the individual only cares for its personal interest, nature, lacking the help of an agent to police law and order, is depending on the selection of the fittest genome to bring about stability. Not playing at all is not an option; not playing it right causes instability, so over a long history of animal societies, only the ones where the individual player keeps playing the right hand, can survive. “Playing the right hand,” means the individual chooses the right strategy of passing on its gene and experience, or gives support to somebody else’s success in return for benefits. Which raises a question. Given the seemingly irrational character of some of our taboos, does our morality not defy such explanation? It is all good and well to ascribe to a code of high-minded ethics – the morals we believe we should observe – but that’s not the morals we actually do observe. So what is really at the core of our moral makeup? How is it, that on the whole even politicians and compulsive liars speak more often the truth than a falsehood? Why is it, that with nothing but our self-interest at heart, more often than not, we play the right hand without even knowing what the right hand should be? John Mynard-Smith (*1920, Evolution and the Theory of Games, Cambridge University Press, 1983) used game theory as the mathematical tool to calculated the probability values when different types of moral behavior come into conflict with each other. People usually know that it pays to appear playing nice and being cooperative. It doesn’t really matter whether they really mean it. What counts is what they are getting in return and how this is affecting the other players. As it so happens, the more restrained player is likely to play the better hand over the reckless daredevil. However the same does not apply to the player who tries avoiding risks altogether. To love, in evolutionary terms, does make sense; so does self-sacrifice, and not only when parents defend their brood. And some of the strategies are far from obvious. Homophobes sometimes frame an argument based, as they think, on evolution. Gay people obviously don’t contribute to the gene pool or do they? Among meerkats only the alpha male is breeding; all the other males are recruited for nursing and protecting the little ones, which gives this species a distinct advantage over competing mongoose societies where every male has a stake in the breeding lottery. This doesn’t mean that all sexual activities suddenly cease for the males. Homosexuality is a phenomenon not just among the human species. I heard somebody saying, that 80% of all people are actually bisexual, but follow the conventions of their culture, and that only 10% of each are either invariably gay or straight. I don’t know about these figures, but I think the general concept is correct. Even celibacy can be socially beneficial. Individual awareness for the need of unselfish behavior is not really necessary. In fact all our moral observances come down to a purely mathematical theorem. If you choose to avoid every risk and be the timid “dove,” never willingly engaging in conflict, the prospects seem grim in an environment of uninhibited aggression. But it is exactly this kind of environment that also curtails the chances of the hawkish aggressor; used to reckless escalation of every conflict no matter what. The “hawk” is running the risk of being taken out of the game the very first time he encounters someone retaliating in kind, especially if the rest of society continues settling their differences in conventional, less aggressive tussles. There is usually a phase of intermittent posturing – watch the encounter of two territorial toms in your backyard – before things get really serious, and this is what the “bluffer” is looking for. He tries to achieve submission by pretending to be a "hawk." In actual fact he is only probing the responses and at the slightest hint of retaliation will immediately retreat, but won’t stop to increase the stakes as long as no resistance is forthcoming. A more cautious approach than that of the “bully” whose first move is more assertive, trying to shock and awe without actually intending to go the full monty, and therefore leavng him in danger of suffering punishment if the opponent continues escalating. On balance the "bluffer" will never suffer injury, but the "hawk," the "retaliator" and even the "bully" will elbow him out of the game and therefore they are more successful in their pursuits. We notice the importance of posturing. You got to advertise your intentions, whether you follow up or not; it is the social buffer that helps preventing injuries on every level. It also is keeping you honest. Whatever your reason for doing something on the sly, you are courting a greater retaliatory risk. People are not in a forgiving mood if they find their trust being betrayed, even in relatively small matters. President Clinton would probably never have been impeached had he been open about his affairs right from the start. Machiavelli already knew that a sexual peccadillo is the shortest road to popularity for a politician, and as far as the American public is concerned, the polls during the Lewinsky affair confirm Machiavelli’s dictum. (Mrs. Clinton of course had a different view on this matter.) For the “dove,” seeking allies, you, as the “retaliator,” are the only hope of ever getting the better out of a conflict other than against the peers. A “hawk” as an ally may be strong and overpowering, but lacking a concept of compensation and quid pro quo, he may one day turn on the junior partner. Historically only one strategy has proven to provide long term stability, the one of the "retaliator." Never begin a fight, always be the one to end it. If challenged, go through the paces to the very end, but keep it social if the opposition is stepping down, and among your peers, of course, be a pussycat. |
در زندگی بازیهای بسیاری انجام میدهیم ‘ خواه برای سرگرمی و کودکانه ‘ خواه برای سوداگری و سود آوری ‘ یا حتی عاشقانه‘