08-27-2009, 04:32 AM
Zitat:I've never seen a description of "coin flipping strategy" which takes the above science into count. When it's a true 50-50 toss, there is no strategy. But if we take it as granted, or at least possible, that a coin flip does indeed exhibit a 1% or more bias, then the following rules of thumb might apply.<!-- m --><a class="postlink" href="http://www.codingthewheel.com/archives/the-coin-flip-a-fundamentally-unfair-proposition">http://www.codingthewheel.com/archives/ ... roposition</a><!-- m -->
1. Always be the chooser, if possible. This allows you to leverage Premise 1 or Premise 2 for those extra percentage points.
2. Always be the tosser, if you can. This protects you from virtuoso coin-flippers who are able to leverage Premise 6 to produce a desired outcome. It also protects you against the added randomness (read: fairness) introduced by flippers who will occasionally, without rhyme or reason, invert the coin in their palm before revealing. Tricksy Hobbitses.
3. Don't allow the same person to both toss and choose. Unless, of course, that person is you.
4. If the coin is being tossed, and you're the chooser, always choose the side that's initially face down. According to Premise 1, you'd always choose the side that's initially face up, but most people, upon flipping a coin, will invert it into their other palm before revealing. Hence, you choose the opposite side, but you get the same 1% advantage. Of course, if you happen to know that a particular flipper doesn't do this, use your better judgment.
5. If you are the tosser but not the chooser, sometimes invert the coin into your other palm after catching, and sometimes don't. This protects you against people who follow Rule 4 blindly by assuming you'll either invert the coin or you won't.
6. If the coin is being spun rather than tossed, always choose whichever side is lightest. On a typical coin, the "Heads" side of the coin will have more "stuff" engraved on it, causing Tails to show up more frequently than it should. Choosing Tails in this situation is usually the power play.
7. Never under any circumstances agree to a coin spin if you're not the chooser. This opens you up to a devastating attack if your opponent is aware of Premise 2.
(Der zitierte Artikel ist noch etwas dicker und hat noch eine Herleitung)
:mrgreen: