Alice in Borderland is one of the mangas that I have enjoyed the most in recent years, it is part of my Top 10 Recommended Animes and Mangas, and although it captures the psychology of all the characters very well and forces you to empathize with them and suffer in each game, precisely What hooked me the most to continue reading was the originality of each test, especially highlighting the King of Diamonds game., which I found remarkably interesting.
This article contains spoilers from the official Alice in Borderland manga. The series on Netflix hasn't gotten to this point yet, and you'll be skipping a lot of information. If you are really interested in knowing the outcome, you can read the official manga, or start reading the manga where the Netflix series ends.
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King of Diamonds Game – Alice in Borderland
Only five people (four people plus the king of diamonds), and only one of them will be the one who comes out alive and with the King of Diamonds card, inheriting his position if he so wishes.
The game "Beauty contest» proposed by the King of Diamonds himself is inspired by a game described by the economist Colin F. Camerer in his book Behavioral Game Theory, who in turn was inspired by the experiment described by John Maynard Keynes with this same name. As a result of this game, the “2/3 of the Average” experiment, proposed by Alain Ledoux, later emerged. In the original Beauty Contest, a game model is explained in which participants have to vote for the most beautiful girl according to different facial features, and the participant who is closest to the average of all the facial features voted wins. Thus, To win you don't need to vote for what seems most attractive to you, but rather what you think seems most attractive to the rest.
Beauty Contest – Rules:
- All players select a number between 0 and 100 in the given time.
- The average of the values will be multiplied by 4/5 (0.8).
- The person who chooses a number closest to the one calculated wins.
When each round ends:
- All losers will lose one point.
- Once a player reaches -10 points, they will be bathed in burning acid.
- The last player left will survive.
- A new rule is introduced for each eliminated player.
At first it may seem like a test in which the most influential thing is the luck of each player, since your result does not depend solely on you, but will also be influenced by the other four players. The King of Diamonds was also betting his life that he would win, so if it were a game of luck, he would have only a 20% chance of having maintained his title throughout history.
One of the participants also mentioned that although it is not entirely a game of luck, it is closer to being a test of Hearts. However, nothing could be further from the truth, this game is not about analyzing the psychology of others. Since all the rules of the game are based on mathematics The one who is most precise in measuring the rationality of his rivals will win.
Participants
Game Analysis
Beauty Pageant Round 1
At first, Daimon Hinako thinks that all of her classmates will choose the number 50, since they are all incredibly intelligent and this is the safest option. In this way the average would also be 50, and multiplied by a factor of 0.8, as indicated by the rules of the game, the final result would be 40. If she chooses the number 40 from the beginning, the average of the five numbers will be 48, which multiplied by 0.8 would end up resulting in 38.4, and she would win. Simple, right? (I hope so, because this is the superficial part of the game).
To Daimon Hinako's surprise, she was the furthest from getting it right. All his teammates deduced that they were all going to go down until choosing the number 40, and that the final result would be 32, the question is: if another player chooses 32 as an answer, it may even be interesting to choose 28, 29 or 30, lowering the average a little more to favor you over the rest. In this way the King of Diamonds chooses the number 29 and becomes the only player who does not receive a penalty that turn.
If you think about it, following the previous reasoning this time it is possible that everyone thinks that the other players will choose the number 32, and in this way the final answer will become 32 x 0.8 = 25.6. But if they also think that, everyone will choose 26, and the final answer would be 20.8. Following this logical reasoning, it is very risky to choose anything other than 0. Without a doubt, the final answer favors those who round down, since everything will be multiplied by 0.8.
Another way to reach this conclusion is the following:
If you cannot choose numbers above 100, the result can never be above 80, and thus choosing a number above 80 does not make sense. If everyone knows that choosing something greater than 80 is meaningless, 80 would become the limit, but then no result would ever be greater than 64, so choosing a number greater than 64 would be meaningless, etc... until reaching the conclusion. that choosing a number other than 0 would not make any sense.
Round 2 of the Beauty Pageant
Something very interesting happens here, and since they are all highly intelligent players, it doesn't take them long to understand that if everyone chooses 0 as an answer, no one will ever win. In this way, everyone decides to bet on going down little by little towards 0. In fact, going down to 0 suddenly can be a risky move, since if you have not all reached the same conclusion, and for example the chosen numbers They are 0, 0, 0, 1 and 21, whoever has chosen 1 will end up winning.
This is when the real game begins: you have to analyze the first round of each of your opponents and measure their level of rationality.
Benzo the mathematician, and Keiichi the King of Diamonds played a very smart round. On the other hand, the medical student played a completely rational round while the analyst and the lender made good calculations but also let themselves be carried away by instinct.
What number would you choose for the second round?
This time everyone thinks similarly: 32 has been the number around which the first round was played, so the final result when choosing 32 would now be 26. Everyone will think the same, and will look for a number around 20. The question is... How correct will the rest of the players be and how much will they try to lower the average?
Once again we see how the lender is briefly influenced by her instinct, while the other players have had a fairly successful round. However, The King of Diamonds is once again the one who has best understood the way others play.
Round 3 of the Beauty Pageant
In the third round something similar happens: the girl is not good at choosing mathematically exact results, and tends to round off, on the other hand the mathematician usually chooses the most rational results, without taking his competitors into account too much, while the doctor and the analyst They are beginning to read well all the plays except those of the King of Diamonds.
After the third round, Keiichi, international lawyer and current King of Diamonds is the only one who has not lost points.
Round 4 of the Beauty Pageant
In the fourth round, only the lawyer and the doctor play their cards well: they have realized that the lender follows a different thought process from the rest, and that the mathematician has very beautiful calculations but has not managed to understand the way of thinking. of the lender.
Even so The King of Diamonds once again gives the most accurate bet, and still does not lose points.
Round 5 of the Beauty Pageant
What would you choose for the fifth round?
It is a slightly confusing round, because they have been going down steps until they reach this point, in which everyone should play around 0. In fact, there were two players who went ahead and already chose 0 in the previous round. At this point they reach the Nash equilibrium, a game theory concept that refers to cases in which no player can obtain benefits by changing their strategy. Everyone had foreseen this in the second round: now if someone chooses a number other than 0 they have a high probability of losing.
Everyone's bets for this round were:
Everyone could be choosing 0 until they were forced to take a chance on some round to finish the game at some point and not starve.
The doctor quickly realizes this and it doesn't take him even a single round to destroy Nash's Balance. Also this round the girl wins, who has continued to launch risky bets even at this time.
I think the King of Diamonds was going to bet on number 1 in the next round, once everyone had realized that voting for 0 was useless.
Beauty Pageant Round 6
Now the question is… how does the game continue?
As you have been able to deduce, in the next round everything becomes a little more chaotic: the girl consciously decides to lose this round in order to make it clear that choosing 0 was no longer an option. On the other hand, the mathematician bets that no one was going to risk their points again, the analyst understands that everyone was going to choose a number above zero, and again the doctor and the lawyer are the only ones who keep up with the girl, anticipating that he was going to spend this turn creating more chaos. Still, in this round the doctor wins.
Round 7 of the Beauty Pageant
The next round is the doctor who chooses the number 100 again, and It's the girl who wins again. Meanwhile, the mathematician continues betting on 0, thinking that everyone was going to value his life this time, above anything else.
Beauty Pageant Round 8
Already in the eighth round the mathematician decides to change strategy, and bet on 36, understanding that the final results were high and no one was betting on the Nash Equilibrium.
To their surprise, neither player chooses to lose on purpose this round, so the results stabilize a bit and both the doctor and the lawyer emerge victorious from this bet.
After this eighth round in which the tie between Keiichi and Shuntarou, the rest of the game is no longer based on searching for an answer oriented so that all players will choose the same number as a reference; For this ninth round everyone knows each other enough to try to accurately find the choice of each of their opponents.
Rounds 9 and 10 of the Beauty Contest
By the end of the tenth round, the mathematician and the analyst lose their lives., without having won a single round.
Several more rules are added at the end of the game.. The most interesting is that if several players choose the same number, all those players lose. This way you can avoid possible scenarios in which everyone bets on 0, or 1...
I don't want to continue analyzing it much more because the dynamics of the game have already been seen, and in the remaining rounds very interesting psychological deductions are made, but not so related to the game itself.
The possibilities for the three remaining people to play are as follows:
Playing Strategy
It would be very curious to have the opportunity to play this game with your friends, or online, like someone playing a game of poker... but what?What strategies would be the most optimal to win in this Diamonds game??
It may still seem that against unknown rivals on the internet this game would be 100% lucky, however, you have several rounds to get to know your opponents, and the main premise is that everyone will want to win. With that data in mind you can develop strategies and calculations like those of the King of Diamonds.
The best strategy certainly seems to be to gauge the rationality of your opponents and act accordingly. It's not a great help, but I don't know what other strategies could be used either. If you have any ideas, leave them in the comments.
END – Alice in Borderland's King of Diamonds Game
This has been a summary and analysis of the Beauty Pageant game, put into practice in a theoretical scenario of Alice in Borderlands, after its mathematical proposal by Keynes in 1936, and its transformation into a "game" format by Colin F. Camerer a few years later. .
You can leave a comment with your opinion, or highlighting any information that you think is incorrect or can be improved; I will be happy to read it.
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