Now I will give my new class an insight into the game before the first class (for computer majors, I will emphasize the importance of information flow, and other majors can also contact each other because there are games everywhere). The prisoner's dilemma also implies that people should communicate more, so that the result will be the best (communication is not enough, if the prisoner contacts 10 minutes in advance, the result may still be the same). The following examples are for students.
It's a little long I suggest you watch the movie A Beautiful Mind.
Before studying supply chain management, it is suggested to study game theory first. By studying game theory, we can see the importance and necessity of implementing supply chain management in enterprises.
My opinion on game theory
In this lesson, let's do an intelligence test first: pirates divide jewels.
Five pirates took 100 priceless jewels, exactly the same. So now it's time to divide the dirty (pirates don't divide them according to our usual method, and everyone wants the most), so someone put forward a method and everyone agreed. This method is: draw lots to arrange five pirates as 1, 2, 3, 4 and 5, starting with the pirate 1, let him come up with a distribution plan and decide how much each person will get, and then if more than 50% (including 50%) of the pirates agree, he will follow his distribution plan, but if this standard is not met,
Conditions:
1. Every pirate just wants to get the maximum benefit.
2. All pirates are rational.
This is a game problem. You can think about it. If you were a pirate, which pirate would you like to be? If you were the first pirate, how would you divide this 100 jewel?
The following question is a bit boring. Let me talk about the concept of games. If you are not interested, you can start analyzing and answering piracy questions.
First, the concept of the game
The game is simply playing chess. The game is that many people play chess. Like chess, gobang, poker and so on are the most direct games.
Game refers to the process that each participant chooses his own strategy (action) based on the information he has under the constraints of certain game rules, based on the environmental conditions of direct interaction, so as to maximize the benefits and minimize the risk cost.
Games exist in all aspects of our lives, from what clothes to wear when we get up in the morning, what breakfast to eat, teachers giving lectures, listening to lectures or chatting ... these are all games.
More than 2000 years ago, The Art of War was not only a military work, but also the earliest monograph on game theory. After 2000, Mao Zedong proposed that "people don't commit crimes against me, and I don't commit crimes; If people attack me, I will attack "is also a game.
Now give everyone five minutes to think about piracy ... The answer is 98 0 1 0 1.
Now let's look at another example: let 10000 people choose a number from 1- 100, and finally choose the one closest to half of everyone's average to win.
Generally speaking, if there are enough people, the numbers will be scattered, so the final average should be close to 50, so I should choose 25 = 50/2, which has a better chance of winning.
But on second thought, I know other people know this, so if they all choose 25, then I should choose 12.5 = 25/2.
In the same way, others will think of this, so constantly, and finally everyone chooses 1. There are no winners.
Second, the type of game.
1. Games can be divided into dynamic games and static games.
Static game: refers to the players taking actions at the same time, or although there is a sequence, the latter actor does not know the strategy of the former actor. Like the average problem mentioned earlier.
Dynamic game: refers to the action sequence of both parties, and the latter actor can know the strategy of the former actor. Like the piracy problem mentioned earlier.
Third, why should we learn games?
As we have said, everything anyone does has a game factor in it.
Paul samuelson, winner of the Nobel Prize in Economics, said:
If you want to be a valuable person in modern society, you must have a general understanding of game theory.
It can also be said that if we want to win logistics management, we must learn game theory; If you want to win life, you should also learn game theory, and even feelings are related to games.
Don't talk about theory, now learn the game through a few examples:
1, the "pig's income" in economics
This example is about: there are two pigs, a big pig and a little pig in the pigsty. There is a pedal on one side of the pigsty. Every time you step on the pedal, a small amount of food will fall on the feeding port on the other side of the pigsty far from the pedal. If one pig steps on the pedal, the other pig has a chance to eat the food that has fallen on the other side first. As soon as the pig steps on the pedal, the big pig will eat all the food just before the pig runs to the trough; If the big pig steps on the pedal, there is still a chance for the little pig to run to the trough and compete for the other half before eating the fallen food.
So, what strategy will the two pigs adopt? The answer is: Piglets will choose the "hitchhiking" strategy, that is, they will wait comfortably in the trough; The big pig ran tirelessly between the pedal and the trough, just for a little leftovers.
What is the reason? Because, little pigs can get nothing by pedaling, but they can eat food without pedaling. For piglets, it is always a good choice not to step on the pedal whether the big pig does or not. On the other hand, the big pig knows that the little pig can't step on the gas pedal. It's better to step on the accelerator by himself than not to step at all, so he has to do it himself.
The phenomenon of "the little pig is lying down and the big pig is running" is caused by the rules of the game in the story. The core indicators of the rules are: the number of things falling each time and the distance from the pedal to the feeding port.
If we change the core indicators, will there be the same scene of "pigs lying down and big pigs running" in the pigsty? Give it a try.
Change scheme 1: reduction scheme. Feeding is only half of the original weight. As a result, neither the little pig nor the big pig kicked. The little pig will step on it, and the big pig will finish the food; If the big pig steps on it, the little pig will finish the food, too. Whoever pushes means contributing food to each other, so no one will have the motivation to push.
If the goal is to make pigs pedal more, the design of this game rule is obviously a failure.
Variation scheme 2: incremental scheme. Feed twice as much as before. As a result, both the little pig and the big pig can pedal. Anyone who wants to eat will kick. Anyway, the other party won't eat all the food at once. Piglets and big pigs are equivalent to living in a materialistic society with relatively rich materials, and their sense of competition is not very strong.
For the designer of the rules of the game, the cost of this rule is quite high (providing two meals at a time); Moreover, because the competition is not strong, it has no effect to let the pigs push more.
Variant 3: Decreasing plus shifting scheme. Feed only half the original weight, but at the same time move the feeding port near the pedal. As a result, both the little pig and the big pig pushed hard. Those who wait will not eat, and those who work hard will get more. Every harvest is just a flower.
This is the best solution for game designers. The cost is not high, but the harvest is the biggest.
The original story of "Smart Pig Game" inspired the weak (pigs) in the competition to wait for the best strategy. But for the society, the allocation of social resources when piggy hitchhiked is not optimal, because piggy failed to participate in the competition. In order to make the most efficient allocation of resources, the designers of rules don't want to see anyone hitchhiking, so does the government, and so does the boss of the company. Whether the phenomenon of "hitchhiking" can be completely eliminated depends on whether the core indicators of the rules of the game are set properly.
For example, the company's incentive system design is too strong, and it is still holding shares and options. All the employees in the company have become millionaires. Not to mention the high cost, the enthusiasm of employees is not necessarily high. This is equivalent to the situation described in the incremental scheme of Smart Pig Game. However, if the reward is not strong and the audience is divided (even the "little pigs" who don't work), the big pigs who have worked hard will have no motivation-just like the situation described in the first phase of the "Smart Pig Game". The best incentive mechanism design is like changing the third scheme-reducing staff and changing shifts. Rewards are not shared by everyone, but for individuals (such as business proportion commission), which not only saves costs (for the company), but also eliminates the phenomenon of "hitchhiking" and can achieve effective incentives.
2. Prisoner's Dilemma Game
In game theory, a famous example of dominant strategic equilibrium is Tucker's "prisoner's dilemma" game model. This model tells us the story of a policeman and a thief in a special way. Suppose two thieves, A and B, commit a crime together, enter the house privately and are caught by the police. The police put the two men in two different rooms for interrogation. For each suspect, the policy given by the police is that if a suspect confessed his crime and handed over the stolen goods, the evidence was conclusive and both of them were convicted. If another suspect also confessed, they were each sentenced to eight years in prison; If another suspect denies it without confession, he will be sentenced to two years in prison for obstructing official duties (because there is evidence to prove that he is guilty), and the confessor will be released immediately after eight years of commutation. If both of them deny it, the police can't convict them of theft because of insufficient evidence, but they can each be sentenced to 1 year in prison for trespassing.
Analysis: omitted, a can be obtained through analysis. No matter how B chooses, it is wise to choose confession. Similarly, A also chooses to confess, and we know that the best solution should be denial.
This is that the maximization of individual interests cannot achieve the maximization of overall interests. This problem was first discovered by Nash. When each party chooses a strategy, there is no "collusion" (collusion). They just choose the best strategy for themselves, regardless of social welfare or the interests of any other opponents. In other words, this strategy combination is composed of the best strategy combination of all participants (also called parties and participants). No one will take the initiative to change their strategy in order to gain greater benefits for themselves. The "prisoner's dilemma" has a wide and profound significance. The conflict between individual rationality and collective rationality and everyone's pursuit of their own interests lead to a "Nash equilibrium", which is also an unfavorable outcome for everyone. Both of them think of themselves first in the strategy of frank denial, so they are bound to serve long sentences. Only when everyone thinks of each other first, or colludes with each other, can we get the result of the shortest imprisonment. Nash equilibrium first challenges Adam Smith's "invisible hand" principle. According to Smith's theory, in the market economy, everyone starts from the purpose of self-interest, and finally the whole society achieves the effect of altruism. Let's review the famous saying of this economic sage in The Wealth of Nations: "By pursuing (personal) self-interest, he often promotes social interests more effectively than he actually wants to do." A paradox of the principle of "invisible hand" is drawn from Nash equilibrium: starting from self-interest, the result is not self-interest, neither self-interest nor self-interest. This is the fate of two prisoners. In this sense, the paradox put forward by Nash equilibrium actually shakes the cornerstone of western economics. Therefore, from Nash equilibrium, we can also realize a truth: cooperation is a favorable "self-interest strategy".
A beautiful mind is about Nash.
If all four of them go after that beautiful girl, she will definitely put on airs and ignore anyone; Chasing other girls at this time will not be accepted by others, because no one wants to be inferior. "Suddenly, Nash said to himself," but if the four of them go after other girls first, the beautiful girl will feel isolated and it will be much easier to go after her.
Friends
Rachel and Ross like confession games.
Of course, TV plays pursue perfect results, and how to deal with love games in reality.
From the typical game problem of "prisoner's dilemma", we can deeply understand the necessity of implementing "supply chain management" in enterprises. (omitted)