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Ludic Fallacy

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Re: Ludic Fallacy

#11

Post by marvin »

FeepingCreature wrote: post #10
baxtr wrote: post #8

Earlier quoted context omitted.

That’s actually exactly what I was going to say. Of course you should update your priors continuously and thus evolve your model. A model is never perfect but it’s the best approximation to reality we have. In the end, Fat Tony has a model in his head, too.

Right - "assume at the start that the coin is fair - you are free to update the assumption as you go" is a different thing than they said. Usually "assume that" assumptions are meant to hold throughout the question. As Randall says, "communicating badly and then acting smug when you're misunderstood is not cleverness."

I think the central point here is that «assume that» is fine when working with a math problem, but can kill you in real life.

If you’ve just lost two billion dollars, or killed 200,000 people in a preventable war, no one cares that the assumptions were reasonable.

Re: Ludic Fallacy

#12

Post by pmoriarty »

sudhirj wrote: post #5

The nicest example of this I've seen is that Tim Ferris won a kickboxing championship without being a kickboxer, https://www.martialdevelopment.com/how-to-win-kickboxing-wro... The fallacy is that winning a world championship at kickboxing must mean that you're an excellent kickboxer, but nope.

This reminds me of Derren Brown (a magician) winning simultaneous chess games against grandmasters...

https://www.youtube.com/watch?v=rIAXIubSTkc

Re: Ludic Fallacy

#13

Post by aaron695 »

I think The Emperor Wears No Clothes.

This has no meaning.

But it's vague and meaningless enough you can pull it out when you want to prove something involving statistics or models not working, which they mostly don't.

Re: Ludic Fallacy

#14

Post by buran77 »

sudhirj wrote: post #5

The nicest example of this I've seen is that Tim Ferris won a kickboxing championship without being a kickboxer, https://www.martialdevelopment.com/how-to-win-kickboxing-wro... The fallacy is that winning a world championship at kickboxing must mean that you're an excellent kickboxer, but nope.

I'm not sure what kind of championship that was but for an experienced fighter having a 30 pound "handicap" versus an inexperienced one should amount to no real life disadvantage. Don't underestimate what a 165 lbs person's tibia can do to a 195 lbs person's head on even thigh. There's no "hack" to not getting your lights knocked out with one punch/kick from a good fighter 30 lbs lighter than you. And tricking the weigh in is something that has been done since the second ever weigh-in.

The fact that he was able to hold off experienced fighters, even if they were below his weight class, means he was plenty qualified to be there despite his very modest self assessment.

[Edited from here] He seems to be an actual fighter under Dave Camarillo but the framing of this story, that he's just an average "stuff my face with peanut butter sandwiches, tricked the weigh-in" kind of guy, is just in order to sell his "life hacks" books.

All I can find is that 1999 was the second year for the championship which could mean not very strong competition. But there's no mention of him in any Wushu/Sanda/Sanshou championship. He also used to claim that he is a "Cage fighter in Japan, vanquisher of four world champions (MMA)" (since removed from his page). Being a 4 time world champion would have contradicted his "just a regular guy using life hacks" premise. Without an actual record of him winning that "Chinese Kickboxing National Championships 1999" I guess he's just peddling the same "tricks" from his book. One of them might be "just say you did it".

Re: Ludic Fallacy

#15

Post by l0b0 »

FeepingCreature wrote: post #6

Isn't the first example extremely bullshit? > A third party asks them to "assume that a coin is fair, i.e., has an equal probability of coming up heads or tails when flipped. I flip it ninety-nine times and get heads each time. What are the odds of my getting tails on my next throw?" Istm that Fat Tony here gets the right answer to the wrong question. Whether we should assume this is not part of the question. That th…

Yeah, the only thing it proves is that when a scientist says "assume X" to another scientist the common understanding is that it means "in a situation where it is given that X is true, no matter how ridiculous that might be in real life."

As for more reasons why this is bullshit, see the gambler's fallacy and the Monty Hall problem – intuition is often terrible at arriving at the right prediction.

Re: Ludic Fallacy

#16

Post by TheOtherHobbes »

FeepingCreature wrote: post #6

Isn't the first example extremely bullshit? > A third party asks them to "assume that a coin is fair, i.e., has an equal probability of coming up heads or tails when flipped. I flip it ninety-nine times and get heads each time. What are the odds of my getting tails on my next throw?" Istm that Fat Tony here gets the right answer to the wrong question. Whether we should assume this is not part of the question. That th…

But the assumption is the point. When you have enough data to suggest your model is wrong, you should throw away the model and the assumptions it's based on, not the data.

The fact that your model can be justified as technically correct is irrelevant. When the data doesn't fit the model any more, the supposed absolute correctness of the textbook model blocks your ability to understand what's happening.

This isn't even about games, but about whether it's possible to be open-minded enough to consider that simple textbook "solutions" are not guaranteed to be a good fit for real problems - especially if you don't understand their limitations or the assumptions they're based on.

And it doesn't just apply to statistics.

Re: Ludic Fallacy

#17

Post by thom »

pmoriarty wrote: post #12
sudhirj wrote: post #5

The nicest example of this I've seen is that Tim Ferris won a kickboxing championship without being a kickboxer, https://www.martialdevelopment.com/how-to-win-kickboxing-wro... The fallacy is that winning a world championship at kickboxing must mean that you're an excellent kickboxer, but nope.

This reminds me of Derren Brown (a magician) winning simultaneous chess games against grandmasters... https://www.youtube.com/watch?v=rIAXIubSTkc

As in, he got another kickboxer to pretend to be him and fight in his place?

Re: Ludic Fallacy

#18

Post by basdftrewq »

FeepingCreature wrote: post #10
baxtr wrote: post #8

Earlier quoted context omitted.

That’s actually exactly what I was going to say. Of course you should update your priors continuously and thus evolve your model. A model is never perfect but it’s the best approximation to reality we have. In the end, Fat Tony has a model in his head, too.

Right - "assume at the start that the coin is fair - you are free to update the assumption as you go" is a different thing than they said. Usually "assume that" assumptions are meant to hold throughout the question. As Randall says, "communicating badly and then acting smug when you're misunderstood is not cleverness."

The point is that in real life problems it's more important to throw away ridiculous "assume that"s than having very neat models.

Re: Ludic Fallacy

#19

Post by aspenmayer »

buran77 wrote: post #14
sudhirj wrote: post #5

The nicest example of this I've seen is that Tim Ferris won a kickboxing championship without being a kickboxer, https://www.martialdevelopment.com/how-to-win-kickboxing-wro... The fallacy is that winning a world championship at kickboxing must mean that you're an excellent kickboxer, but nope.

I'm not sure what kind of championship that was but for an experienced fighter having a 30 pound "handicap" versus an inexperienced one should amount to no real life disadvantage. Don't underestimate what a 165 lbs person's tibia can do to a 195 lbs person's head on even thigh. There's no "hack" to not getting your lights knocked out with one punch/kick from a good fighter 30 lbs lighter than you. And tricking the we…

Thai kickboxing and BJJ isn’t a joke. Neither is physics and bone density increases through training, same with muscle fiber density and reaction time. I can go on. Training matters.

Re: Ludic Fallacy

#20

Post by gwd »

baxtr wrote: post #8
FeepingCreature wrote: post #6

Isn't the first example extremely bullshit? > A third party asks them to "assume that a coin is fair, i.e., has an equal probability of coming up heads or tails when flipped. I flip it ninety-nine times and get heads each time. What are the odds of my getting tails on my next throw?" Istm that Fat Tony here gets the right answer to the wrong question. Whether we should assume this is not part of the question. That th…

That’s actually exactly what I was going to say. Of course you should update your priors continuously and thus evolve your model. A model is never perfect but it’s the best approximation to reality we have. In the end, Fat Tony has a model in his head, too.

I think the Ludic Fallacy would be better described as, "A tendency to be overconfident that you know what the game is." If you read the Black Swan, what Taleb is mainly railing against are people who are completely confident that because they have a model, that it must therefore be correct, and refuse to remember all the caveats, and what could happen if their model is wrong.
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