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Parrondo's Paradox: How two ugly parents can make a beautiful baby

datagenetics.com

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Re: Parrondo's Paradox: How two ugly parents can make a beautiful baby

#11

Post by tborg »

> (I think I’ve probably lost a good number of people in this post already, so if you’re still reading this, I assume you’re familiar with Eigenvectors).

Actually, no! I was kind of hoping that by reading this section, I might find out about them. Why write a blog post section specifically targeted at those readers for whom it holds no new information? The responsible thing to do here, if you really didn't feel like explaining some key component of your discussion, would have been to provide a reference to someone else's explanation. Now it feels like you were wasting my time -- 'oh, hey kid, wasn't talking to you!'

Also, as others above have mentioned, the generalized introduction (a way to make 2 losing games into a winner!) does not lead intuitively into the extremely case-specific exposition.

Re: Parrondo's Paradox: How two ugly parents can make a beautiful baby

#12

Post by intellegacy »

Can someone explain the uptown / downtown train story to me?

If the downtown train arrives and departs a few minutes after the uptown train arrives and departs, respectively, why would he take the downtown train more? It seems to me that if he missed both trains, then he would take the uptown train, as it would arrive earlier.

Re: Parrondo's Paradox: How two ugly parents can make a beautiful baby

#13

Post by GavinB »

Isn't it a little sketchy to have one of the "games" be a game that takes into account outside information like your balanace?

Here's another "paradox":

Game A: You lose a dollar every time.

Game B: If the last game you played was game A, you win a million dollars. Otherwise, you lose a dollar.

AAAAAAA... loses, BBBBBBB... loses, but ABABABABA... makes you rich!

Suddenly it doesn't seem so paradoxical to me.

Re: Parrondo's Paradox: How two ugly parents can make a beautiful baby

#14

Post by SonicSoul »

adamc wrote: post #6

It didn't seem like much of a paradox to me, since game B is really two different games, and interleaving plays of game A changes the likelihood of playing B1 vs. B2. Interesting, perhaps, but not terribly unintuitive.

the un-intuitive part is that the odds supposedly flip in your favor just by alternating 2 games with negative odds.

Re: Parrondo's Paradox: How two ugly parents can make a beautiful baby

#15

Post by tocomment »

GavinB wrote: post #13

Isn't it a little sketchy to have one of the "games" be a game that takes into account outside information like your balanace? Here's another "paradox": Game A: You lose a dollar every time. Game B: If the last game you played was game A, you win a million dollars. Otherwise, you lose a dollar. AAAAAAA... loses, BBBBBBB... loses, but ABABABABA... makes you rich! Suddenly it doesn't seem so paradoxical to me.

I was thinking the same thing. Is there a version that makes it a paradox?

Re: Parrondo's Paradox: How two ugly parents can make a beautiful baby

#16

Post by brucehart »

intellegacy wrote: post #12

Can someone explain the uptown / downtown train story to me? If the downtown train arrives and departs a few minutes after the uptown train arrives and departs, respectively, why would he take the downtown train more? It seems to me that if he missed both trains, then he would take the uptown train, as it would arrive earlier.

He is saying the opposite. The downtown train arrives on the hour and the uptown train arrives at 5 minutes after the hour.

Re: Parrondo's Paradox: How two ugly parents can make a beautiful baby

#17

Post by n09n »

intellegacy wrote: post #12

Can someone explain the uptown / downtown train story to me? If the downtown train arrives and departs a few minutes after the uptown train arrives and departs, respectively, why would he take the downtown train more? It seems to me that if he missed both trains, then he would take the uptown train, as it would arrive earlier.

You are correct, he messed up telling the story.

Re: Parrondo's Paradox: How two ugly parents can make a beautiful baby

#18

Post by [deleted] »

sigkill wrote: post #4
slug wrote: post #2

Babies are made through love, love is beautiful, ergo babies are beautiful. Q.E.D. (I read the whole post, it was an interesting read)

Extending your discussion, love is nothing but chemicals firing in our brain. Maybe human beings are evolved to trigger release chemicals in the brain when certain conditions are met, which could possibly be deterministic? I agree that each person is different, but we're all same in the same way. Think of the attraction to the opposite sex as a seeded random number. Sure, we don't know the seed but if you know a pers…

[deleted]

Re: Parrondo's Paradox: How two ugly parents can make a beautiful baby

#19

Post by n09n »

brucehart wrote: post #16
intellegacy wrote: post #12

Can someone explain the uptown / downtown train story to me? If the downtown train arrives and departs a few minutes after the uptown train arrives and departs, respectively, why would he take the downtown train more? It seems to me that if he missed both trains, then he would take the uptown train, as it would arrive earlier.

He is saying the opposite. The downtown train arrives on the hour and the uptown train arrives at 5 minutes after the hour.

No, he does not say the opposite:

>even though the trains arrive with the same frequency, the downtown train departs just a few minutes after the uptown train has departed. Because of this, there is only a narrow time window in which the man is able to get on the uptown train.

He should say it like you suggested though.

Re: Parrondo's Paradox: How two ugly parents can make a beautiful baby

#20

Post by alexfoo »

brucehart wrote: post #16
intellegacy wrote: post #12

Can someone explain the uptown / downtown train story to me? If the downtown train arrives and departs a few minutes after the uptown train arrives and departs, respectively, why would he take the downtown train more? It seems to me that if he missed both trains, then he would take the uptown train, as it would arrive earlier.

He is saying the opposite. The downtown train arrives on the hour and the uptown train arrives at 5 minutes after the hour.

The description has it the other way.

"The solution is that, even though the trains arrive with the same frequency, the downtown train departs just a few minutes after the uptown train has departed. Because of this, there is only a narrow time window in which the man is able to get on the uptown train."

s/after/before/ to fix the explanation.

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