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Jon MW
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« Reply #15 on: January 15, 2012, 05:06:00 PM » |
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Nope. Too many other factors for that to be 50/50.
like what? |
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Jon "the British cowboy" Woodfield
2011 blonde MTT League August Champion
2011 UK Team Championships: Black Belt Poker Team Captain - - runners up - -
5 Star HORSE Classic - 2007 Razz Champion
2007 WSOP Razz - 13/341
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mulhuzz
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« Reply #16 on: January 15, 2012, 05:20:46 PM » |
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Nope. Too many other factors for that to be 50/50.
one suspects you could take a Chernoff bound to determine which side is biased and then take a decent sample based on that bias....although I'm probably overegging it for a random question on a poker forum?  |
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gatso
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« Reply #17 on: January 15, 2012, 05:48:01 PM » |
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write a number on it using a pen, maybe a green one. then ask someone to guess whether it's an odd or an even number. they'll probs get it right about 50% of the time
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If you get to the yeasty clunge you've gone too far
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doubleup
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« Reply #18 on: January 15, 2012, 06:08:26 PM » |
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write a number on it using a pen, maybe a green one. then ask someone to guess whether it's an odd or an even number. they'll probs get it right about 50% of the time
the date on the coin could be odd or even, so you wouldn't need to spend the coin to buy a green pen |
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mulhuzz
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« Reply #19 on: January 15, 2012, 06:28:44 PM » |
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Nope. Too many other factors for that to be 50/50.
one suspects you could take a Chernoff bound to determine which side is biased and then take a decent sample based on that bias....although I'm probably overegging it for a random question on a poker forum? confirmed overegged it. sigh. |
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gatso
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« Reply #20 on: January 15, 2012, 06:45:46 PM » |
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I figured the date thing would be biased to the last full year as there'd be more in circulation
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If you get to the yeasty clunge you've gone too far
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EvilPie
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« Reply #21 on: January 15, 2012, 06:50:41 PM » |
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Rather than flip the coin just take it out of your pocket and place it on a table.
Assuming you don't know which way the bias works I'm pretty sure that'd be 50/50.
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Motivational speeches at their best:
"Because thats what living is, the 6 inches in front of your face......" - Patrick Leonard - 10th May 2015
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gatso
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« Reply #22 on: January 15, 2012, 07:08:31 PM » |
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Or we could just flip it and call heads or tails. As we don't know what way it's biased it's still 50/50 whether we get it right or not
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If you get to the yeasty clunge you've gone too far
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AndrewT
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« Reply #23 on: January 15, 2012, 07:27:30 PM » |
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Take the coin and throw it at cf's head. You'll either hit him or you won't - 50/50.
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mulhuzz
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« Reply #24 on: January 15, 2012, 07:27:51 PM » |
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Or we could just flip it and call heads or tails. As we don't know what way it's biased it's still 50/50 whether we get it right or not
nah - what if the coin is 100% biased? |
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gatso
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« Reply #25 on: January 15, 2012, 07:31:49 PM » |
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Or we could just flip it and call heads or tails. As we don't know what way it's biased it's still 50/50 whether we get it right or not
nah - what if the coin is 100% biased? Even if it's double headed/tailed we're still 50/50 to get it right if we don't know which one. Ignorance ftw |
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If you get to the yeasty clunge you've gone too far
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mulhuzz
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« Reply #26 on: January 15, 2012, 07:35:36 PM » |
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ok, say 90% it's heads and 10% it's tails.
we pick heads 50% and tails 50% over 100 trials (assume no variance and that 100 is a big enough number to make results match expectation perfectly)
when we pick tails, we're never right 50% of the time....
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gatso
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« Reply #27 on: January 15, 2012, 07:50:06 PM » |
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agreed but I'm only talking about a one off single flip
question asked 'How can we use this coin to get a genuine 50/50 chance?' and that's what we'd get once
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If you get to the yeasty clunge you've gone too far
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Cf
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« Reply #28 on: January 15, 2012, 08:30:59 PM » |
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agreed but I'm only talking about a one off single flip
question asked 'How can we use this coin to get a genuine 50/50 chance?' and that's what we'd get once
Nope. You're making an assumption that neither person knows about the bias, and this might not always be the case. The correct answer will always work, no matter the bias (as long as it's not doublesided/100% of course). |
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Blue text
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doubleup
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« Reply #29 on: January 15, 2012, 08:51:13 PM » |
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Nope. You're making an assumption that neither person knows about the bias, and this might not always be the case.
We don't know which side, nor do we know the size of the bias. How can we use this coin to get a genuine 50/50 chance?
So that was the royal we and not a co-operative effort from a pair of tossers? |
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