Friday, January 19, 2007

Superstitious? No; then same.

Hey Folks,

Last time I talked about what to do during the pre-game meeting. One finer detail with the flip is what to pick when the discs are actually in the air. With two discs it’s a probability thing, and I’m no probability guy.

For those of you unfamiliar how we flip to make decisions, two discs are flipped in the air, and one person calls same or different. Same means both discs land the same way (both up or both down). Different means the discs land opposite to each other (one up, one down).

Pictured Above: More WUCC. This time the women's final with what looks like 4 of 6 wearing tights. Courtesy of James.

This is what I know, but I can’t remember who taught me the lesson. It was back in my Pong captaining days.

If a flipped disc doesn’t favour landing up or down when flipped in the air, then it wouldn’t matter if you call same or different. If the disc, however, does favour either up or down, then it means that both discs favour up or down (in the same fashion), and the odds favour “same”. Either way, you might as well call “same”, and get an advantage if there is one.

This does bring up an issue. There is no scientific proof that a disc favours one side or the other on a flip, but again, it is possible that the disc favours a side. Since there might be an advantage, ultimate should adopt a fair flip so there is no advantage to the caller, and I think that means bringing the coin as the flipping device of choice (though it too might favor heads or tails).

That, or let me have the choice when we meet next pre-game.



parinella said...

Discs are highly asymmetrical, so I would be more surprised if it was 50/50 than if one way was more likely.

There are several alternatives:
1. Rocham.
2. Test of skill. Two players throw toward a cone at the same time, closer one wins.
3. Assign one player HT, assign the other player TH. HH and TT are do-overs.

This has been covered many, many times on rsd.

Sideline Engineer said...

In a wind, a flipped disc is more likely to end up down, as the lip catches the wind. The stronger the wind, the more likely the disc will end up down.

Anonymous said...

Better yet:


Perfect for warming up your argument skills and taking stock of the mental game of your opponent.

Anonymous said...

to repeat what parinella said
"This has been covered many, many times on rsd."

the only real news here is how one coherent brain failed to do a better job on the topic than 70 raving incoherent rsd posters

kirker said...
This comment has been removed by a blog administrator.
kirker said...

it's really only a valid point if you assume 100% of TCO readers read RSC faithfully. the fact that it has been covered so many times elsewhere might reflect that it is of either great interest or concern ... which is really all the more reason to discuss it again here.

aj said...

I think you're discounting the psychological advantage of the wild man strategy. Even if the disc lands on side 60% of the time (way too high I would guess) - we're only looking at a 52-48 advantage for same. So, I usually go with different in order to gain the psychological edge. When you say "different" you convince your opponent that you have no conscience - an image you can use to your advantage for the entire game.


parinella said...

When my opponent calls "different", I expect that he has no knowledge of probabilities and risk/reward, rather than that he does know about it and chooses to disregard it in favor of psych. Wrt choosing O or D, I feel the same way, but to a lesser extent, since it is entirely possible that there is something unique about the first point of the game that can lead to negative chaining. That is, it's possible that if you start on O and get broken that you are psychologically doomed for the rest of the day, but it's not that way if you start on D, get scored on, and then get broken in your first O point.