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

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.""

Comments

well... one way to solve it

[UU7]

heads they're wrong.
tails they're right.

Re:well... one way to solve it

[ArmenTanzarian]

The scientists have asked that you start the coin heads side down.

Re:well... one way to solve it

[Virtex]

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?

Oh Darn...

[jwthompson2]

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?

From the article

[Anonymous Coward]

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.

Of course there's a bias

[Anonymous Coward]

Bias:

Heads 49.9%

Tails 49.9%

Coin becomes
Self-aware 00.2%

Re:Let it hit the ground...

[Sogol]

No, the coin always hits the ground beacuse of gravity. Heads I'm right, Tails you're wrong ;)

Re:Thank God we still have

[ultrafunkula]

Good old rock. Nothing beats rock.

Re:Thank God we still have

[murphyslawyer]

Poor, predictable ultrafunkula. Always chooses rock.

Law School

[Prince Vegeta SSJ4]

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:Tax dollars at work, one coin at a time

[Anonymous Coward]

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

[FauxPasIII]

> 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 !

Re:Tax dollars at work, one coin at a time

[Anonymous Coward]

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

Research materials budget - 0.01 $

Re:Tax dollars at work, one coin at a time

[InfiniteWisdom]

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

[Rhubarb Crumble]

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

[FauxPasIII]

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

Bill produces movies ?