BBO Robot Hands Why does BBO insist they are completely random
#22
Posted 2015-January-21, 07:13
If there really is a bias in favor of finesses not working, one should incorporate this into one's overall strategy of play. Let me know if you suddenly become a master of the robot games by playing for all finesses to fail.
When I was a new player (back in the 70's) people complained all the time about computer hands. I rarely hear that anymore. But every so often someone complains about a bad break by breaking out the old "darn computer hands" complaint.
#23
Posted 2015-January-21, 13:42
Bbradley62, on 2015-January-20, 21:55, said:
On those 105 hands, you had 49 opportunities to finesse for a missing Ace (when you had the K but not the Q of the suit in question). 28 of the 49 Aces were onside.
On those 105 hands, you had 51 opportunities to finesse for a missing King. Sometimes you held AQJ of the suit between the two hands (in which case "onside" meant in front of the Ace) and sometimes you held A in one and Q in the other without the J (in which case "onside" meant in front of the Q. 31 of the 51 missing Kings were onside.
On those 105 hands, you had one-way finesses for missing Queens 36 times, and the missing Queen was onside 13 times.
So, on those 105 hands you had 136 opportunities to finesse for missing A/K/Q (not that you took all those finesses, or even that it was a good idea to do so) and the missing honor was onside 72 times (53%).
I looked at the same hands, and my count was similar, 73 out of 134, actually slightly more optimistic than your count. I then included all of the tournaments since I made my posting, and the finesses for the players were 53% successful, the highest I have ever seen for that many tournaments in all of my reviews. I think we can agree that there is no significant difference in how we evaluate finesses. Below is a copy of the spreadsheet of the 20 tournaments I evaluated before I posted. (It is interesting that I had the highest success rate after posting my comment, but I will leave conspiracy theory to others.) If you have time to check the previous 20, I would like to know what numbers you came up with.
Finesses
Player Robots Total
Date Tourn Win Lose Win Lose Win Lose
31-Dec 5357 4 6 1 4 7
1-Jan 9466 5 6 2 3 8 8
1-Jan 9705 6 7 1 7 7
1-Jan 864 2 3 2 3
2-Jan 7203 4 6 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 1 5 1
6-Jan 3864 3 7 1 3 8
6-Jan 4027 7 1 1 7 2
8-Jan 3839 7 12 7 12
8-Jan 4589 3 11 2 2 5 13
10-Jan 1077 2 7 2 2 9
11-Jan 5532 3 9 2 1 4 11
11-Jan 6086 4 3 1 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
Pct 39.2% 64.9% 38.3%
#24
Posted 2015-January-21, 13:56
tx10s, on 2015-January-21, 13:42, said:
Finesses
Player Robots Total
Date Tourn Win Lose Win Lose Win Lose
31-Dec 5357 4 6 1 4 7
1-Jan 9466 5 6 2 3 8 8
1-Jan 9705 6 7 1 7 7
1-Jan 864 2 3 2 3
2-Jan 7203 4 6 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 1 5 1
6-Jan 3864 3 7 1 3 8
6-Jan 4027 7 1 1 7 2
8-Jan 3839 7 12 7 12
8-Jan 4589 3 11 2 2 5 13
10-Jan 1077 2 7 2 2 9
11-Jan 5532 3 9 2 1 4 11
11-Jan 6086 4 3 1 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
Pct 39.2% 64.9% 38.3%
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.
#25
Posted 2015-January-21, 14:39
ArtK78, on 2015-January-21, 07:13, said:
If there really is a bias in favor of finesses not working, one should incorporate this into one's overall strategy of play. Let me know if you suddenly become a master of the robot games by playing for all finesses to fail.
When I was a new player (back in the 70's) people complained all the time about computer hands. I rarely hear that anymore. But every so often someone complains about a bad break by breaking out the old "darn computer hands" complaint.
That was great sarcasm, but ignores the data. Obviously, if all finesses were offside, the game would be easier. Obviously, everyone plays the same hand, but I'm sure the experts (not me) would know how to adjust their strategy for the bias built into a dealing program. I have already seen that at BBO by all the people who bid the frequent "cheap" slams that the robot program puts out. When I say cheap slams, the average slam hand that I have looked at (about 30) has an average of 29 HCP and barely over 30 total points. Additionally, I have looked for hands with over 30 points that do not make slam, and they are very few and far between.
#26
Posted 2015-January-21, 14:51
tx10s, on 2015-January-21, 13:56, said:
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
#27
Posted 2015-January-21, 14:57
#28
Posted 2015-January-21, 15:00
Bbradley62, on 2015-January-20, 22:01, said:
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.
#29
Posted 2015-January-21, 15:01
tx10s, on 2015-January-21, 14:51, said:
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
Thank you to whoever fixed my post
#30
Posted 2015-January-21, 15:03
barmar, on 2015-January-20, 10:00, said:
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.
#31
Posted 2015-January-21, 15:05
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.
#32
Posted 2015-January-21, 15:07
barmar, on 2015-January-21, 14:57, said:
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
#33
Posted 2015-January-21, 15:13
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
#35
Posted 2015-January-22, 12:06
barmar, on 2015-January-21, 15:05, said:
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.
#36
Posted 2015-January-22, 13:50
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?
Psyche (pron. sahy-kee): The human soul, spirit or mind (derived, personification thereof, beloved of Eros, Greek myth).
Masterminding (pron. mstr-mnding) tr. v. - Any bid made by bridge player with which partner disagrees.
"Gentlemen, when the barrage lifts." 9th battalion, King's own Yorkshire light infantry,
2000 years earlier: "morituri te salutant"
"I will be with you, whatever". Blair to Bush, precursor to invasion of Iraq
#37
Posted 2015-January-22, 15:30
helene_t, on 2015-January-21, 15:03, said:
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.
#38
Posted 2015-January-22, 16:00
barmar, on 2015-January-22, 15:30, said:
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).
#39
Posted 2015-January-22, 19:18
1eyedjack, on 2015-January-22, 13:50, said:
#40
Posted 2015-January-22, 19:36
tx10s, on 2015-January-19, 16:23, said:
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 work
On that set of hands, you're annoyed because E/W gets more HCPs than North South
On 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...