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The Coin Flip: A Fundamentally Unfair Proposition? (2009)

econ.ucsb.edu

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Re: The Coin Flip: A Fundamentally Unfair Proposition? (2009)

#11

Post by PhantomGremlin »

wozniacki wrote: post #10
heyitsnick wrote: post #7

"1% may not sound like a lot, but it's more than the typical casino edge in a game of blackjack or slots." The house edge for slots games is anywhere from 2% to 15%+ and is one of the worst bets you can make in the casino. Blackjack, video poker and some bets on craps are the only times in a casino where the house edge shrinks to below 1%.

Blackjack, video poker and some bets on craps are the only times in a casino where the house edge shrinks to below 1%. Care to cite your source for this or are you a gaming industry insider?

There's no need for a source. It's common knowledge. Many books, websites, and research papers have extensively studied those games.

Edward Thorp is a mathematician who did a lot of analysis about blackjack over 50 years ago.[1] He's a seminal figure in this field.

Here's one site I recall mostly because it has a memorable name: http://wizardofodds.com/

[1] https://en.wikipedia.org/wiki/Beat_the_Dealer#History

Re: The Coin Flip: A Fundamentally Unfair Proposition? (2009)

#12

Post by PhantomGremlin »

danieltillett wrote: post #9
zw123456 wrote: post #8

The most interesting part to me was this "A coin will land on its edge around 1 in 6000 throws, creating a flipistic singularity." ( https://en.wikipedia.org/wiki/Flipism ) I assume that was as the result of using the tossing machine, but I really thought it would not have been that frequent.

I have this happen a lot when tossing on wooden floors with a gap between the boards - basically the coin gets stuck in the gap. My brother and I got quite good at deliberately doing this. I have never had it happen on a flat surface and I must have tossed 10,000 of coins in my youth.

I once attempted to hand a quarter to a convenience store clerk. Somehow we dropped it during the exchange. The coin rolled about 8 feet and went thru a tiny gap between two large cardboard boxes on the floor.

I'm sure I could have stood there for an hour attempting to drop a coin onto the floor and have it roll into that gap, and I would have failed.

Re: The Coin Flip: A Fundamentally Unfair Proposition? (2009)

#15

Post by windowsworkstoo »

wozniacki wrote: post #10
heyitsnick wrote: post #7

"1% may not sound like a lot, but it's more than the typical casino edge in a game of blackjack or slots." The house edge for slots games is anywhere from 2% to 15%+ and is one of the worst bets you can make in the casino. Blackjack, video poker and some bets on craps are the only times in a casino where the house edge shrinks to below 1%.

Blackjack, video poker and some bets on craps are the only times in a casino where the house edge shrinks to below 1%. Care to cite your source for this or are you a gaming industry insider?

It says it right on the card on the table that explains the min/max bets (in Aus at least). Also, it's basic stats which can be applied depending the house rules.

Re: The Coin Flip: A Fundamentally Unfair Proposition? (2009)

#16

Post by danieltillett »

PhantomGremlin wrote: post #12
danieltillett wrote: post #9

Earlier quoted context omitted.

I have this happen a lot when tossing on wooden floors with a gap between the boards - basically the coin gets stuck in the gap. My brother and I got quite good at deliberately doing this. I have never had it happen on a flat surface and I must have tossed 10,000 of coins in my youth.

I once attempted to hand a quarter to a convenience store clerk. Somehow we dropped it during the exchange. The coin rolled about 8 feet and went thru a tiny gap between two large cardboard boxes on the floor. I'm sure I could have stood there for an hour attempting to drop a coin onto the floor and have it roll into that gap, and I would have failed.

I had a similar situation in which a coin I tossed managed to end up stuck in a small gap in the celling. I remember having to get up on a chair on top of a table (I must have been under 10 at the time) to get it out. Good times :)

Re: The Coin Flip: A Fundamentally Unfair Proposition? (2009)

#17

Post by ChristianBundy »

PhantomGremlin wrote: post #11
wozniacki wrote: post #10

Earlier quoted context omitted.

Blackjack, video poker and some bets on craps are the only times in a casino where the house edge shrinks to below 1%. Care to cite your source for this or are you a gaming industry insider?

There's no need for a source. It's common knowledge. Many books, websites, and research papers have extensively studied those games. Edward Thorp is a mathematician who did a lot of analysis about blackjack over 50 years ago.[1] He's a seminal figure in this field. Here's one site I recall mostly because it has a memorable name: http://wizardofodds.com/ [1] https://en.wikipedia.org/wiki/Beat_the_Dealer#History

> There's no need for a source. It's common knowledge. Many books, websites, and research papers have extensively studied those games.

It's obviously not common knowledge to the person that's asking the question. :~) Thanks for the source though.

Re: The Coin Flip: A Fundamentally Unfair Proposition? (2009)

#18

Post by thret »

letstryagain wrote: post #6
plonh wrote: post #4

A commenter explains that the most interesting claim (51% bias) is not explained correctly in the article. Humans flipping a coin add a bit of precession (spin) that biasses the toss. The "odd/even time in the air" analysis is incorrect -- that only matters if it is possible to stop the coin before the first flip.

Yep. To see this, consider a coin flipped into the air so that it's tilted 45 degrees with the floor and spinning only around the vertical axis. To a casual observer it will appear as if the coin is tumbling but in fact one side faces up 100% of the time.

This is a trick that can be learnt with practice. If you spend a lot of time around gamblers, don't ever accept a coin toss proposition.

Re: The Coin Flip: A Fundamentally Unfair Proposition? (2009)

#19

Post by thret »

PhantomGremlin wrote: post #12
danieltillett wrote: post #9

Earlier quoted context omitted.

I have this happen a lot when tossing on wooden floors with a gap between the boards - basically the coin gets stuck in the gap. My brother and I got quite good at deliberately doing this. I have never had it happen on a flat surface and I must have tossed 10,000 of coins in my youth.

I once attempted to hand a quarter to a convenience store clerk. Somehow we dropped it during the exchange. The coin rolled about 8 feet and went thru a tiny gap between two large cardboard boxes on the floor. I'm sure I could have stood there for an hour attempting to drop a coin onto the floor and have it roll into that gap, and I would have failed.

The same is true for every possible outcome, that one just happened to be memorable.

Re: The Coin Flip: A Fundamentally Unfair Proposition? (2009)

#20

Post by shuriu »

This video from Numberphile goes in depth about this: https://www.youtube.com/watch?v=Obg7JPd6cmw . The guy talking, is Persi Diaconis, is the main author of the paper this article is based upon.

He also has done research on the randomness of shuffling cards: https://www.youtube.com/watch?v=AxJubaijQbI . Pretty cool stuff!

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