Quote:
Originally Posted by jake
I'm pretty sure this isn't quite right. Odds of being dealt 2 suited cards are 23.5%.(reference ) Hearts specifically must therefore be about 6%. 9 players in hand so odds (before flop) are about 54% that one player has hh.
Odds that a player with 2 suited cards flops flush are 0.84% (see same reference). Therefore odds that 1 player flopped a flush on this board is 0.84 * .54 = 0.45% (1 in 200).
Not trying to be a wise ass... but let me know if you think this calc is closer.
On first point your calculation ignores the fact that we know 5 cards that aren't in anyone else's hand, 3 hearts and 2 non-hearts so 10 hearts left of the remaining 47 in the deck. Odds that any given person with a random hand has 2 hearts is 10/47*9/46 which is about 4%. As noted that is an underestimate though because people are more likely to play suited hands and if we know one player doesn't have 2 hearts it makes it more likely that another player does.
On second point, that's the chance that you flop a flush if you hold two suited cards. that includes all flops, so doesn't take into account that our flop has 3 hearts. Once you know the flop has 3 hearts the relevant question is whether any person has 2 hearts in their hand. Doesn't matter how likely they were to flop a flush once a monotone flop comes out.
Just generally, your second number can't be right. If it really was the case that we're only up against a flopped flush 1 out of every 200 times, it would mean we would be shocked to be against a flush here. That can't be the case on a monotone board. It may not be probable that we are facing a flush 9-way, but it wouldn't be very surprising.