Science of the coin-toss: Bias in Heads-or-Tails

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Science of the coin-toss: Bias in Heads-or-Tails

Posted by CmdrTaco on Tuesday March 2, 2004 @04:20AM from the didn't-gildenstern-prove-that-already dept.

MrSharkey writes " An interesting article published in Science News puts a new scientific spin on the outcome of the venerable coin-toss. "A new mathematical analysis suggests that coin tossing is inherently biased: A coin is more likely to land on the same face it started out on.""

36 of 559 comments (clear)

well... one way to solve it by UU7 · 2004-03-02 04:21 · Score: 5, Funny

heads they're wrong.
tails they're right.
1. Re:well... one way to solve it by ArmenTanzarian · 2004-03-02 04:22 · Score: 5, Funny
  
  The scientists have asked that you start the coin heads side down.
2. Re:well... one way to solve it by scumbucket · 2004-03-02 04:25 · Score: 3, Funny
  
  Actually we need to flip a coin to determine that. Wait........
  
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3. Re:well... one way to solve it by DeadSea · 2004-03-02 04:38 · Score: 3, Funny
  
  Heads their right.
  Tails you're wrong.
4. Re:well... one way to solve it by Virtex · 2004-03-02 07:29 · Score: 5, Funny
  
  Someone once told me it was like this:
  
  Heads: Gonna get me some head
  Tails: Gonna get me some tail
  
  So either way you win. I don't get it, though, since everytime I try this, the coin lands on its edge. Seriously, what are the odds of that?
  
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Thank God we still have by frenetic3 · 2004-03-02 04:21 · Score: 4, Funny

rock-paper-scissors to settle the disputes of mankind. And drunken boxing.

-fren

--
"Where are we going, and why am I in this handbasket?"
1. Re:Thank God we still have by ultrafunkula · 2004-03-02 04:29 · Score: 5, Funny
  
  Good old rock. Nothing beats rock.
2. Re:Thank God we still have by murphyslawyer · 2004-03-02 04:36 · Score: 5, Funny
  
  Poor, predictable ultrafunkula. Always chooses rock.
  
  --
  I ain't evil, I'm just good looking.
3. Re:Thank God we still have by Snowdog668 · 2004-03-02 04:44 · Score: 3, Funny
  
  "But they're very sharp scissors".
  
  --
  I wouldn't say I'm a bad gambler but the last time I went to Vegas I even lost a buck on the soda machine.
Oh Darn... by jwthompson2 · 2004-03-02 04:22 · Score: 5, Funny

And the society shaking ramifications of this are what? We will stop tossing coins before football games and instead have a pocket sized random number generator and the teams pick a number?

--
Even if I knew that tomorrow the world would go to pieces, I would still plant my apple tree. -Martin Luther
1. Re:Oh Darn... by mgs1000 · 2004-03-02 04:28 · Score: 3, Funny
  
  Football leagues will have to consult a magic 8-ball to determine the proper course of action.
From the article by Anonymous Coward · 2004-03-02 04:23 · Score: 5, Funny

Their preliminary data suggest that a coin will land the same way it started about 51 percent of the time.

I wonder what their margin of error was.
1. Re:From the article by standard+method · 2004-03-02 04:38 · Score: 4, Funny
  
  +/- 2 percent, I think.
  
  ("What does that even mean?" "Quiet, brain.")
  
  --
  "I'll be a killer whale, when I grow up"
  -Wintersleep
Interesting, but .... by IamGarageGuy+2 · 2004-03-02 04:24 · Score: 3, Funny

Who gets the funds to study these projects? I want a grant to study something like this. I can probably come up with a hypothesis like, hmmm, do strippers like drunks or sober people more. Wheres's my money !!!

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1. Re:Interesting, but .... by Moeses · 2004-03-02 04:34 · Score: 4, Funny
  
  Who gets the funds to study these projects? I want a grant to study something like this.
  
  I think this is what you study after your grant proposal has been refused and the only thing left in the department treasury is a quarter.
80,000 geeks tossing at home now! by Anonymous Coward · 2004-03-02 04:25 · Score: 4, Funny

I just don't want to think about it!
Of course there's a bias by Anonymous Coward · 2004-03-02 04:25 · Score: 5, Funny

Bias:

Heads 49.9%

Tails 49.9%

Coin becomes
Self-aware 00.2%
yay! by marine_recon · 2004-03-02 04:25 · Score: 3, Funny

step one: go to vegas
step two: bet on coin flipping
step three: PROFIT!

wait, that makes too much sense.
dang

--
Jack the sound barrier. Bring the noise.
Heads Again! by rwiedower · 2004-03-02 04:26 · Score: 4, Funny

I bet Rosencrantz is pissed to find this out!
Re:Let it hit the ground... by Sogol · 2004-03-02 04:26 · Score: 5, Funny

No, the coin always hits the ground beacuse of gravity. Heads I'm right, Tails you're wrong ;)
Re:Butter-side down by Anonymous Coward · 2004-03-02 04:29 · Score: 3, Funny

That is, of course, unless you staple it to the back of a cat ...
Needs more testing... by peterprior · 2004-03-02 04:31 · Score: 3, Funny

maybe the folks over at SCO could help test this theory... they're all a bunch of tossers ;) ...I'll get my coat..
Law School by Prince+Vegeta+SSJ4 · 2004-03-02 04:41 · Score: 5, Funny

This sort of reminds me of law school (shudders), where I had a Torts prof who was using a probability (trying to) example. Anyhow, she was explaining that everytime you flip a coin you had a 50/50 chance of heads/tails. She then explained that even so you can still get heads numerous times in a row, proceeded to flip 9 heads in a row. The class was amazed (mostly poly-sci and english majors).
I thought about it for a second, and given the odds of throwing 9 heads in a row AND doing it right as you were using it as an example were astronomically high - stood up and said 'that's a two headed coin'
Teacher smiled and proceeded to show the class the two headed quarter
Re:Let it hit the ground... by IainHere · 2004-03-02 04:43 · Score: 4, Funny

If you've ever watched a football game, you'll notice that the coin always hits the ground. This is done for at least one reason, to prevent tampering by the tosser

Look, referees have a hard enough time as it is, without you throwing in needless insults.
What do you mean always? by raehl · 2004-03-02 04:45 · Score: 3, Funny

I only flip it to the other hand if it doesn't land on the side I want.

--
paintball
Re:Tax dollars at work, one coin at a time by Anonymous Coward · 2004-03-02 04:52 · Score: 5, Funny

Seeing as it's the way Bush determines his foreign policy choices, I think it's very important to study the coin toss.
Re:Tax dollars at work, one coin at a time by FauxPasIII · 2004-03-02 04:58 · Score: 5, Funny

> Seeing as it's the way Bush determines his foreign policy choices,
> I think it's very important to study the coin toss.

Eek ! Somebody please hand him the coin with the "don't bomb" face showing next time !

--
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Re:Tax dollars at work, one coin at a time by Anonymous Coward · 2004-03-02 05:05 · Score: 5, Funny

Somehow I doubt this was the most expensive experiment ever...

Research materials budget - 0.01 $
Re:Let it hit the ground... by HoldenCaulfield · 2004-03-02 05:25 · Score: 3, Funny

hmm, are you suggesting that all I have to do is flip a coin and get tails to disprove the existence of gravity? :P
geeks don't toss coins by Allison+Geode · 2004-03-02 05:57 · Score: 4, Funny

I'm a geek, so I don't toss coins: I roll a d20 instead. 1-10 I win, 11-20 you lose!
Re:Tax dollars at work, one coin at a time by InfiniteWisdom · 2004-03-02 06:01 · Score: 5, Funny

Eek ! Somebody please hand him the coin with the "don't bomb" face showing next time !

Thats not how it works in this white house. His coin says "Bomb Iraq" and "Bomb Syria"
Re:Tax dollars at work, one coin at a time by Rhubarb+Crumble · 2004-03-02 06:07 · Score: 5, Funny

So we need to stop spending money on everything until the deficit is 0? Equivalently, if you've got a mortgage on your house, then you need to stop spending money on all non-essentials like eating out, owning a car, having more than seven sets of clothes (laundry once a week), computers, eating dessert, ...
If you have a mortgage, but your salary more than covers your mortgage payments, you do not have a deficit.
However, if you already can't pay your mortgage and your solution is to move to a bigger house in the hope that by stimulating the housing market it might get you a better-paying job, the US goverment would probably like to hire you as a financial adviser.
Re:Tax dollars at work, one coin at a time by FauxPasIII · 2004-03-02 06:17 · Score: 5, Funny

> Ever seen the movie "Black Hawk Down"? Bill did that.

Bill produces movies ?

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25% Funny, 25% Insightful, 25% Informative, 25% Troll
Re:Tax dollars at work, one coin at a time by Zaph · 2004-03-02 06:48 · Score: 3, Funny

Actually, they turned out a profit by selling their research meterials on ebay:

For Sale: Unique Gambling Penny
Scientifically proven to land on tails 59.439% of the time!*

(*Special throwing instructions included.)

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I'm also a kind of magician/charlatan by exp(pi*sqrt(163)) · 2004-03-02 08:41 · Score: 3, Funny

What I do is write comments on slashdot that look plausible but are actually completely false. I like to use pseudo-science and obscure jargon to back up my arguments and convince the unsuspecting spectator. Sometimes I just make unverifiable claims with an air of authority and that's enough to convince people to give me karma.

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Re:Tax dollars at work, one coin at a time by Guppy06 · 2004-03-02 12:25 · Score: 3, Funny

"if the person who calls the toss never sees the face of the coin upon the toss,"

Then the coin was showing both heads and tails until you resolved it by looking at it.