tx10s Posted January 21, 2015 Author Report Share Posted January 21, 2015 When I posted this, the data columns lined up nicely. When I went back to add a comment, I see that the data does not present well. In each row, the first item is the date, the second is the tournament number. The third is finesses onside for the players, the fourth is finesses offside for the player, the fifth is finesses onside for the robots, the sixth is finesses offside for the robot, the seventh is the sum of finesses onside for the players and offside for the robots (in other words the finesses that favor the player) and the eights data point is the sum of finesses offside for the player and onside for the robots.Sorry, I had blanks instead of zeros, here is the same data again with the zeros, although still not well presented. I have tried several methods without success, so I will see if I can get Google spreadsheets to work. Finesses Player Robots Total Date Tourn Win Lose Win Lose Win Lose 31-Dec 5357 4 6 1 0 4 7 1-Jan 9466 5 6 2 3 8 8 1-Jan 9705 6 7 0 1 7 7 1-Jan 864 2 3 0 0 2 3 2-Jan 7203 4 6 0 1 5 6 3-Jan 3698 3 9 3 1 4 12 4-Jan 9091 7 10 1 2 9 11 4-Jan 92 6 5 4 3 9 9 5-Jan 5308 4 5 7 1 5 12 5-Jan 6810 4 12 1 1 5 13 6-Jan 1798 4 1 0 1 5 1 6-Jan 3864 3 7 1 0 3 8 6-Jan 4027 7 1 1 0 7 2 8-Jan 3839 7 12 0 0 7 12 8-Jan 4589 3 11 2 2 5 13 10-Jan 1077 2 7 2 0 2 9 11-Jan 5532 3 9 2 1 4 11 11-Jan 6086 4 3 1 0 4 4 12-Jan 1855 4 5 5 1 5 10 12-Jan 2753 3 7 4 2 5 11 Totals 85 132 37 20 105 169 Please remember that totals are Wins: Player wins plus robot losses and Losses: Player losses plus robot wins Quote Link to comment Share on other sites More sharing options...
barmar Posted January 21, 2015 Report Share Posted January 21, 2015 Use the "Code" style to post formatted tables. It's in the Other Styles menu. Quote Link to comment Share on other sites More sharing options...
tx10s Posted January 21, 2015 Author Report Share Posted January 21, 2015 Since I don't see how to post the spreadsheet, and my dataset isn't all that big, I'll copy and paste it here, although I'd still appreciate it if someone explained how to post a file. Well, I can't get it to format nice, and I can't find the recent post about how to make nice columns, so I'll try again tomorrow...When I see how to make nice columns, I will try to post more of my data. I am surprised that this forum has no obvious way to post a spreadsheet, or down load any file for that matter. I am hoping there is a way, and one of you experts can tell me. Quote Link to comment Share on other sites More sharing options...
tx10s Posted January 21, 2015 Author Report Share Posted January 21, 2015 Sorry, I had blanks instead of zeros, here is the same data again with the zeros, although still not well presented. I have tried several methods without success, so I will see if I can get Google spreadsheets to work. Finesses Player Robots Total Date Tourn Win Lose Win Lose Win Lose 31-Dec 5357 4 6 1 0 4 7 1-Jan 9466 5 6 2 3 8 8 1-Jan 9705 6 7 0 1 7 7 1-Jan 864 2 3 0 0 2 3 2-Jan 7203 4 6 0 1 5 6 3-Jan 3698 3 9 3 1 4 12 4-Jan 9091 7 10 1 2 9 11 4-Jan 92 6 5 4 3 9 9 5-Jan 5308 4 5 7 1 5 12 5-Jan 6810 4 12 1 1 5 13 6-Jan 1798 4 1 0 1 5 1 6-Jan 3864 3 7 1 0 3 8 6-Jan 4027 7 1 1 0 7 2 8-Jan 3839 7 12 0 0 7 12 8-Jan 4589 3 11 2 2 5 13 10-Jan 1077 2 7 2 0 2 9 11-Jan 5532 3 9 2 1 4 11 11-Jan 6086 4 3 1 0 4 4 12-Jan 1855 4 5 5 1 5 10 12-Jan 2753 3 7 4 2 5 11 Totals 85 132 37 20 105 169 Please remember that totals are Wins: Player wins plus robot losses and Losses: Player losses plus robot winsThank you to whoever fixed my post Quote Link to comment Share on other sites More sharing options...
helene_t Posted January 21, 2015 Report Share Posted January 21, 2015 If there's a tie for the best hand among the other seats, we pick one of them at random. I don't see how this could result in a finesse bias, though.If you were more likely to swap with East than with West when EW are tied for best hand, it would produce losing finesses for declarer. Quote Link to comment Share on other sites More sharing options...
barmar Posted January 21, 2015 Report Share Posted January 21, 2015 In the "Robot finesse" column, are these cases where the robot took a finesse and it won or lost, or are they cases where the robot COULD have taken a finesse, and it would have won or lost. With AQxx opposite a singleton, and sufficient transportation and ruffing power, the robots often try to ruff out the K rather than just take the finesse, especially if the bidding indicates strength in the hand behind the AQ. So it probably takes fewer finesses than you do, and takes them in cases where they're more likely to succeed. Basically, I think what you're seeing is that the robots are better at calculating the odds and using them to guide their play. This is the kind of thing computers are good at. Quote Link to comment Share on other sites More sharing options...
tx10s Posted January 21, 2015 Author Report Share Posted January 21, 2015 Use the "Code" style to post formatted tables. It's in the Other Styles menu. Finesses Player Robots Total Date Tourn Win Lose Win Lose Win Lose 29-Oct 254 5 8 0 0 5 8 28-Oct 4033 1 6 1 2 3 7 28-Oct 2207 7 10 0 0 7 10 27-Oct 7233 4 8 1 0 4 9 26-Oct 9970 7 2 2 1 8 4 25-Oct 5406 8 8 1 2 10 9 24-Oct 9445 3 9 2 1 4 11 24-Oct 8268 2 9 0 0 2 9 23-Oct 2680 7 5 1 1 8 6 23-Oct 2038 1 3 0 0 1 3 22-Oct 7000 4 4 1 0 4 5 22-Oct 5668 2 5 2 3 5 7 21-Oct 718 6 5 2 6 7 21-Oct 524 4 9 2 4 8 11 20-Oct 3821 4 11 0 0 4 11 19-Oct 9454 5 6 0 0 5 6 19-Oct 7468 4 4 1 1 5 5 18-Oct 2709 6 0 1 1 6 18-Oct 1277 5 7 2 2 7 9 17-Oct 7281 4 6 0 0 4 6 Totals 83 131 18 18 101 149 Thanks for the tip, it works well. Attached is another set of data in my finesses evaluation, dates are 2014 Quote Link to comment Share on other sites More sharing options...
tx10s Posted January 21, 2015 Author Report Share Posted January 21, 2015 Finesses Player Robots Total Date Tourn Win Lose Win Lose Win Lose 29-Oct 254 5 8 0 0 5 8 28-Oct 4033 1 6 1 2 3 7 28-Oct 2207 7 10 0 0 7 10 27-Oct 7233 4 8 1 0 4 9 26-Oct 9970 7 2 2 1 8 4 25-Oct 5406 8 8 1 2 10 9 24-Oct 9445 3 9 2 1 4 11 24-Oct 8268 2 9 0 0 2 9 23-Oct 2680 7 5 1 1 8 6 23-Oct 2038 1 3 0 0 1 3 22-Oct 7000 4 4 1 0 4 5 22-Oct 5668 2 5 2 3 5 7 21-Oct 718 6 5 2 6 7 21-Oct 524 4 9 2 4 8 11 20-Oct 3821 4 11 0 0 4 11 19-Oct 9454 5 6 0 0 5 6 19-Oct 7468 4 4 1 1 5 5 18-Oct 2709 6 0 1 1 6 18-Oct 1277 5 7 2 2 7 9 17-Oct 7281 4 6 0 0 4 6 Totals 83 131 18 18 101 149 Thanks for the tip, it works well. Attached is another set of data in my finesses evaluation, dates are 2014 Here is another set, please excuse my using a reply to post the data, but for some reason, the Code style will not copy a full spreadsheet in the Fast Replay section: Finesses Player Robots Total Tourn Win Lose Win Lose Win Lose 7100 7 5 1 0 7 6 1024 6 6 1 3 9 7 9941 3 9 2 0 3 11 1065 4 4 4 3 7 8 8485 6 10 0 0 6 10 8890 5 4 2 1 6 6 5981 4 5 3 1 5 8 56 3 7 3 1 4 10 564 7 5 2 0 7 7 2156 3 6 2 0 3 8 6396 4 5 2 0 4 7 6703 5 7 0 0 5 7 8371 2 7 1 0 2 8 8482 4 6 0 0 4 6 1936 2 4 2 3 5 6 2075 3 8 0 1 4 8 3540 4 9 1 1 5 10 6698 6 9 1 2 8 10 2715 3 8 0 0 3 8 2936 8 7 2 2 10 9 Totals 89 131 29 18 107 160 Quote Link to comment Share on other sites More sharing options...
barmar Posted January 21, 2015 Report Share Posted January 21, 2015 Try clicking on Use Full Editor. Quote Link to comment Share on other sites More sharing options...
tx10s Posted January 22, 2015 Author Report Share Posted January 22, 2015 In the "Robot finesse" column, are these cases where the robot took a finesse and it won or lost, or are they cases where the robot COULD have taken a finesse, and it would have won or lost. With AQxx opposite a singleton, and sufficient transportation and ruffing power, the robots often try to ruff out the K rather than just take the finesse, especially if the bidding indicates strength in the hand behind the AQ. So it probably takes fewer finesses than you do, and takes them in cases where they're more likely to succeed. Basically, I think what you're seeing is that the robots are better at calculating the odds and using them to guide their play. This is the kind of thing computers are good at.An interesting point, but my finesse calculations were only based on potential finesses, I did not record which finesses were actually taken, as my analysis was done after the hands were played by just looking at the card distribution. Quote Link to comment Share on other sites More sharing options...
1eyedjack Posted January 22, 2015 Report Share Posted January 22, 2015 I am missing something but I don't understand why (excluding total columns) there are 4 columns when I would expect 2. Every finesse that is working for one side is losing for the other. Say you (human) are South, North has AQ and East has K. This is a working finesse for the robot, failing for human. So I would expect this to count +1 in both the "player lose" and "robot win" columns. And I would expect this double entry to balance for each example, so that the total for the player lose column should never depart from the same total for the robot win column. But in your spreadsheet these totals do differ. What's that all about? 1 Quote Link to comment Share on other sites More sharing options...
barmar Posted January 22, 2015 Report Share Posted January 22, 2015 If you were more likely to swap with East than with West when EW are tied for best hand, it would produce losing finesses for declarer.There's a very tiny bias. We use rand()%3 to choose a seat to swap with (0 = W, 1 = N, 2 = E), and rand() returns a number from 0 to 2^31-1. There's one more value whose modulus is 0 than 1 or 2, so there's a 0.00000014% bias towards West. But this has to be multiplied by the probability that EW are tied for best hand in the first place; this can't be any more than 1 in 16, so we're talking about only 0.000000008%. For this to become noticeable you'd have to examine billions of hands, not the few hundred that tx10 and bbradley62 looked at. Quote Link to comment Share on other sites More sharing options...
barmar Posted January 22, 2015 Report Share Posted January 22, 2015 For this to become noticeable you'd have to examine billions of hands, not the few hundred that tx10 and bbradley62 looked at.BTW, we currently generate 10-15 million hands a year. So the total number of hands produced in the entire history of BBO is probably around 100 million. Nowhere close to making that bias noticeable even if we examined every hand (we can't actually do that -- I think our hand archives only go back to around 2007). Quote Link to comment Share on other sites More sharing options...
Bbradley62 Posted January 23, 2015 Report Share Posted January 23, 2015 Every finesse that is working for one side is losing for the other. Say you (human) are South, North has AQ and East has K. This is a working finesse for the robot, failing for human.I don't know OP's methodology, but I over-simplified by only looking at it from the point of view of declarer. Suppose:[hv=pc=n&s=sat63hakqd432c432&w=sk94h5432dakqc765&n=sq852h876d765ckq8&e=sj7hjt9djt98cajt9]399|300[/hv]If NS declares, the spade finesse (hoping to find K in front of the Q) is successful. If EW declares, the spade finesse (hoping to find A in front of the K) is also successful. Quote Link to comment Share on other sites More sharing options...
hrothgar Posted January 23, 2015 Report Share Posted January 23, 2015 If you read the post, the sampling was done on hands that were already dealt. The fact that the finesse split ranged between 38.9% and 41% for sets of twenty tournaments averaging 281 finesses/ open endings with an overall average of 40.0% I felt was significant enough Here's the rub... People are very good at finding patterns in data. If you spend long enough staring at a random set of hands, odds are your going to find something weird about it. On this set of hands, you're upset because the finesses don't workOn that set of hands, you're annoyed because E/W gets more HCPs than North SouthOn some other set of hands, the clubs never break well It is for this reason that you start by specifying a hypothesis, and then test your hypothesis using a completely different data set. This notion is fundamental to any kind of serious analysis... Quote Link to comment Share on other sites More sharing options...
uday Posted January 23, 2015 Report Share Posted January 23, 2015 Being bored, and trying to postpone walking the dog in 34-degree weather, I looked at the set of deals in our live database There are about 137 K deals in there. Mostly very recent deals, a handful of manually uploaded goulash deals, no doubt, but almost exclusively hands dealt by our dealer, including many 'best hand' deals When South had the AQ of spades ( 6774 times ), west had the king 33% of the time and north 33% ( rounding to integers ) When West had the AQ of diamonds ( 4998 times ), north had the K 32% of the time, S had the king 36% of the time When North had the AQ of hearts ( 5054 times), west had the K 31% of the time, south 37% I'm fairly confident it is only bec of best hand that S has the K more often than the others but I don't really see a problem here. If I had to, I could find all the original poster's hands from our archives and do the same thing on those but that would be a bit of a chore. Anyway - it was an interesting exercise, not that I know if i demonstrated anything Quote Link to comment Share on other sites More sharing options...
tx10s Posted January 23, 2015 Author Report Share Posted January 23, 2015 I am missing something but I don't understand why (excluding total columns) there are 4 columns when I would expect 2. Every finesse that is working for one side is losing for the other. Say you (human) are South, North has AQ and East has K. This is a working finesse for the robot, failing for human. So I would expect this to count +1 in both the "player lose" and "robot win" columns. And I would expect this double entry to balance for each example, so that the total for the player lose column should never depart from the same total for the robot win column. But in your spreadsheet these totals do differ. What's that all about?The last two columns cover the total. The first set of 4 columns just break down the finesses by hands played by the player and hands played by the robots, thus the last two columns are sums as you describe. Quote Link to comment Share on other sites More sharing options...
tx10s Posted January 23, 2015 Author Report Share Posted January 23, 2015 Here's the rub... People are very good at finding patterns in data. If you spend long enough staring at a random set of hands, odds are your going to find something weird about it. On this set of hands, you're upset because the finesses don't workOn that set of hands, you're annoyed because E/W gets more HCPs than North SouthOn some other set of hands, the clubs never break well It is for this reason that you start by specifying a hypothesis, and then test your hypothesis using a completely different data set. This notion is fundamental to any kind of serious analysis...I have a hard time taking your comments seriously. I simply looked at various randomly selected tournaments to determine how the finesses were splitting. They were looked at after the fact without recording which actual finesses were taken. I may be only a Bronze Life Master, but I can guarantee you that I can identify finesses and which direction they favor. The fact that the split so consistently averaged 40% over so many sets of tournament is a very strong indication of built in bias. The fact that the split "miraculously" changed to 50% after my posting leaves a strong indication that someone found the bias and "fixed" it. I suspect it was an input variable to the dealing program, but obviously I could never prove it. Quote Link to comment Share on other sites More sharing options...
barmar Posted January 23, 2015 Report Share Posted January 23, 2015 The fact that the split "miraculously" changed to 50% after my posting leaves a strong indication that someone found the bias and "fixed" it. I suspect it was an input variable to the dealing program, but obviously I could never prove it.There have been no recent changes to the dealing code. The last change was when we added the best-hand feature a few years ago. What you're probably seeing is "clumping". Random values are not always evenly distributed in any particular sample, there are often bursts of one type or another. What's important is that you can never predict them. http://en.wikipedia.org/wiki/Poisson_clumping This is a common misconception that many people have about random data. If you look at a picture of lots of dots, and it looks uniformly fuzzy, it's probably NOT random. A random picture would have several concentrations of lightness and darkness. Quote Link to comment Share on other sites More sharing options...
hrothgar Posted January 23, 2015 Report Share Posted January 23, 2015 I have a hard time taking your comments seriously. I simply looked at various randomly selected tournaments to determine how the finesses were splitting. They were looked at after the fact without recording which actual finesses were taken. I may be only a Bronze Life Master, but I can guarantee you that I can identify finesses and which direction they favor. The fact that the split so consistently averaged 40% over so many sets of tournament is a very strong indication of built in bias. The fact that the split "miraculously" changed to 50% after my posting leaves a strong indication that someone found the bias and "fixed" it. I suspect it was an input variable to the dealing program, but obviously I could never prove it. I'll see your "bronze life master" and raise you an MIT graduate degree... The only thing that your posting are doing is demonstrating that you don't even understand what issues are being discussed, let alone being able to make any meaningful contribution. The insinuation that the dealing code was "fixed" based on your expose would be hysterical, if it weren't so sad... Quote Link to comment Share on other sites More sharing options...
barmar Posted January 23, 2015 Report Share Posted January 23, 2015 I'll see your "bronze life master" and raise you an MIT graduate degree...Not to mention the years you spent developing statistical software at The Mathworks. Quote Link to comment Share on other sites More sharing options...
uday Posted January 23, 2015 Report Share Posted January 23, 2015 Richard's credentials are impeccable but ... kumbaya isn't just a river in Egypt, as they don't say. I've seen nuttier bugs than this. I'm convinced there is no bug here, but perhaps I need to demonstrate this with hard data from the archives. When we released our html-based rewrite of our 'Just play bridge' game, someone complained that we kept redealing the same hands ( and that other than that, the game was fun). Took us a while to realize he was serious, but turns out that under certain cache settings, some players were getting the same hands redealt a few times. uday Quote Link to comment Share on other sites More sharing options...
hrothgar Posted January 23, 2015 Report Share Posted January 23, 2015 The fact that the split so consistently averaged 40% over so many sets of tournament is a very strong indication of built in bias. The fact that the split "miraculously" changed to 50% after my posting leaves a strong indication that someone found the bias and "fixed" it. I suspect it was an input variable to the dealing program, but obviously I could never prove it. Here's a less conspiracy minded explanation regarding what happened 1. You noticed a pattern in a given set of hands2. The pattern was real, but it happened by chance3. Accordingly, when you examined a larger set of hands the pattern did not repeat itself If you look back across the thread, you'll note that all my posts emphasize the need to test your hypothesis using a fresh set of hands. Quote Link to comment Share on other sites More sharing options...
barmar Posted January 23, 2015 Report Share Posted January 23, 2015 To make my point about clustering more concrete, suppose you threw a coin 1000 times, and the result is like this: TTTTTTT H T H TTTTT HH T H TTT H T HH T H T H TT HH T HHHH TTTT H TT HH TTTT H T H TT H TTTTT HHHH TT HHHHH T HHHH TT HHH TTTT H T H TT H TT H T HH H TT H T H T HH TT H T H TTTT H T H TTTT H T HH TT HHH T H TT HH T HH T HHHH TT HH T H TTTT H T H T H TT H TTT H TTT HHHHHH T H TTTTT HHH T H T H T HH T H TT HHHHHHH TTT HHHH T HHH TTTT HHH T HH T HHH T HH TT HH T H TTT H TTT H T HH TT H T H T H TT H T H T HHHH T H T H T H TT HH TT H T HHHHH T H T H TTT H TTT H H TTTTT HH TTTT H TT H T HHH TTT HHH T HHHHH TT HHH TT HH T H T HH T HHHH T HHH TTTTTTT H T HHH TTT HH T H TTTTTTT H TTT HHH TTTTTTTT HH T H H T H T HHH TT H TTT HHHH TT H T HHHH T HHH T HH TTTTT H TTT H T H TTT H T HHH TTT H TTTTTTT H T H TTT HHH TTT H TT H T H T HHH T HH TTT H TT HHHH TT T HHHH T HHH TTT HH TT H TT HH T H T H T HH TT H T HH T H T H T H TTT H T H T HH T HHHHH T HHHHHH T HHH TT HHHHH T H T HH T H TTT HH TT HH T H TT HHHH TTT HH T HH T HH T H TT HH T HH TTTT HH T H TTT H T H TT HH T HHHH TTTT H T H TTT HHH TT HHHH TT H T H TT H T HH TT HH T HH TTT HH TT HHHH T HHH TTT HH TTT HH T H T H T H TTT HH TT HH T H TTT HHHHHHHHHH TTT H TTT HHHHHH TT H T HHH TTTTTT H TT HH TTTTT H T H T H T HH TTT H T HHH TT H TT H TTTT H TT HHH TTTT HHH TTTTTT HH T HHHH TT HH T H T H T H TTT HH T HH T HH TT H TTT HHH TT H TTT HHH TTT HHH T H T H TTT H TT H TTTTT HH T HH T H T H T H T HHHH TT H TT H T H T HHHH TTT H TT H TTTTTT HHH T H T H T HH T H TTTTTT H TT HHH T H T H T H T H TTTTT H T HH TTT H TTTT H T H TT HH TT H T H TTTT H TTTT H T H TT HH If you asked most people if this looked random, they'd probably say no, because they see lots of long runs of the same face: two runs of Tails near the beginning, two runs of Heads in the middle of row 8. But this is actually the expected nature of random sequences. If there weren't many sequences like that, it would have to have memory so that it could avoid generating the same results that have been produced recently. If each event is independent there is no memory, so nothing prevents clustering like this. This incorrect intuition is the source of the"gambler's fallacy": if it's been a while since you threw Heads, then Heads are "due" so you should bet on it. Quote Link to comment Share on other sites More sharing options...
tx10s Posted January 25, 2015 Author Report Share Posted January 25, 2015 To make my point about clustering more concrete, suppose you threw a coin 1000 times, and the result is like this: TTTTTTT H T H TTTTT HH T H TTT H T HH T H T H TT HH T HHHH TTTT H TT HH TTTT H T H TT H TTTTT HHHH TT HHHHH T HHHH TT HHH TTTT H T H TT H TT H T HH H TT H T H T HH TT H T H TTTT H T H TTTT H T HH TT HHH T H TT HH T HH T HHHH TT HH T H TTTT H T H T H TT H TTT H TTT HHHHHH T H TTTTT HHH T H T H T HH T H TT HHHHHHH TTT HHHH T HHH TTTT HHH T HH T HHH T HH TT HH T H TTT H TTT H T HH TT H T H T H TT H T H T HHHH T H T H T H TT HH TT H T HHHHH T H T H TTT H TTT H H TTTTT HH TTTT H TT H T HHH TTT HHH T HHHHH TT HHH TT HH T H T HH T HHHH T HHH TTTTTTT H T HHH TTT HH T H TTTTTTT H TTT HHH TTTTTTTT HH T H H T H T HHH TT H TTT HHHH TT H T HHHH T HHH T HH TTTTT H TTT H T H TTT H T HHH TTT H TTTTTTT H T H TTT HHH TTT H TT H T H T HHH T HH TTT H TT HHHH TT T HHHH T HHH TTT HH TT H TT HH T H T H T HH TT H T HH T H T H T H TTT H T H T HH T HHHHH T HHHHHH T HHH TT HHHHH T H T HH T H TTT HH TT HH T H TT HHHH TTT HH T HH T HH T H TT HH T HH TTTT HH T H TTT H T H TT HH T HHHH TTTT H T H TTT HHH TT HHHH TT H T H TT H T HH TT HH T HH TTT HH TT HHHH T HHH TTT HH TTT HH T H T H T H TTT HH TT HH T H TTT HHHHHHHHHH TTT H TTT HHHHHH TT H T HHH TTTTTT H TT HH TTTTT H T H T H T HH TTT H T HHH TT H TT H TTTT H TT HHH TTTT HHH TTTTTT HH T HHHH TT HH T H T H T H TTT HH T HH T HH TT H TTT HHH TT H TTT HHH TTT HHH T H T H TTT H TT H TTTTT HH T HH T H T H T H T HHHH TT H TT H T H T HHHH TTT H TT H TTTTTT HHH T H T H T HH T H TTTTTT H TT HHH T H T H T H T H TTTTT H T HH TTT H TTTT H T H TT HH TT H T H TTTT H TTTT H T H TT HH If you asked most people if this looked random, they'd probably say no, because they see lots of long runs of the same face: two runs of Tails near the beginning, two runs of Heads in the middle of row 8. But this is actually the expected nature of random sequences. If there weren't many sequences like that, it would have to have memory so that it could avoid generating the same results that have been produced recently. If each event is independent there is no memory, so nothing prevents clustering like this. This incorrect intuition is the source of the"gambler's fallacy": if it's been a while since you threw Heads, then Heads are "due" so you should bet on it. Well Mr. MIT (I graduated from Cal Tech myself), you apparently need a basic lesson in probability. As you know, with one finesse, (or coin flip), there are two possible outcomes, Onside (I will call Y, and Offside, I will call N). With two finesses, the combinations are NN, NY, YN, and YY, thus 25% will have no finesses, 50% will have 1 finesse and 25% will have 2 finesses. I am sure you understand that this can be expanded to any number of finesses, and a basic Excel spreadsheet can calculate the number of combinations for an number of finesses. I found that 20 tournaments had an average of about 280 finesses. 280 finesses have a total of 1.94267E+84 possible combinations for the 281 total outcomes (0 to 280 Y) These average 280 finesses had an average of 112 finesses in favor of the player. There are 9.5056E+80 combinations for 112 or less finesses. Thus, the chance of getting 112 or fewer finesses on side out of 280 total finesses is about 1 in 2000. My data showed the same 1 in 2000+/- outcome (within a fairly narrow margin)all 9 separate times. For your example, the chances of getting 400 or fewer heads in 1000 coin flips is about 1 billion to one. In other words, the greater the number of coin flips or finesses, the less likely the final count will be very far outside (as a percentage of the total) from the middle outcome, as in a bell shaped outcome distribution. When I did the analysis, I was not sure what the outcome would be, I just had a feeling that the hand distributions were not random, and unlike others, I actually accumulated the data to see what the distributions actually were. Your problem is you are looking at small cluster distributions rather than total outcomes, which is what I did.If you would like to tell me what is wrong with my calculations, I am willing to listen. If you think I am lying or did not obtain the data correctly, I posted two sets of 20 tournaments with my calculated outcomes. I do not know if you are associated with BBO, but someone from there can double check my calculations if they want to.BTW, I am not assuming some conspiracy that the finesse distribution just happened to change after my post. I had complained to BBO support service about the distributions and they said that their programmers would look at the issue, so I am assuming someone looked and "corrected" the situation. Since BBO has long insisted that the hands were totally random, I would not expect them to ever admit that they made the change. Quote Link to comment Share on other sites More sharing options...
Recommended Posts
Join the conversation
You can post now and register later. If you have an account, sign in now to post with your account.