July 8, 2017 Chouette Results

We had a pretty good turnout – 7 people total. Initial cast of characters was the regulars: Mark F, Nick, Mark S, Paul, and me. Mark S charmed the gentleman who had taken “our” table before we arrived into moving over one, and received instant karma in that he took the box initially. But then he proceeded to hold it for a full rotation of the field!

About that time, Gints arrived, and so Paul and I split off to play with him at a lower stakes table. Jim showed up shortly thereafter and eventually got suckered into joining the higher stakes table.

The gentleman who Mark S had charmed off chatted about literature, politics, and jokes that were funnier in other languages while we bent over our boards. The lower stakes table was pretty evenly matched – Gints held the box for quite a few games at first, but then we settled into a cycle of pretty regular turnover. Ours broke up just before 5, but the high stakes table was still going – Mark S continuing to reap the karmic benefits of his charm offensive.

Here’s one position that came up that lead to some discussion about the right move. I am black and in the box, and offered a double. Was I right to do so? Would you take?


According to both GnuBG and Extreme Gammon, black is about 70% to win 70.6% or 70.4%, depending which you ask. But it’s a very minor error to double! By doubling, I gave up 0.005 in equity. Note that the gammon chances here are very low, under 1%, and so the Jacoby rule doesn’t provide a rationale for the double. So this is a No Double/Take situation. I forget what happened over the table, but I believe there was one take and one drop.

Gints took a few more pictures, and if he sends them to me I will update the post with any other interesting ones.

Meantime, we’re up again next weekend for a tournament – low RSVP count so far but there’s a week to go. See you there!


Man versus machine

Not surprisingly, I was playing some backgammon against the computer today. What was surprising, to me at least, was the following position came up that got marked as “doubtful” by GnuBG:


Now, I didn’t even think about this one, clearly the right move is 11/7,10/7 and making the 6 prime. But GnuBG said no, 10/6, 9/6 is better. Huh?

GnuBG says 10/6, 9/6 has equity +0.788, 11/7, 10/7 has equity +0.715; a difference of -0.073 and so a blunder! Extreme gammon rates it similarly, 10/6, 9/6 gets +0.797 while 11/7, 10/7 gets +0.736, a difference of -0.061 and again a blunder!

It gets worse for me. After the next exchange of rolls, I was at the following position:


D’uh – clearly 9/2 is the right move. But no, GnuBG says 7/2, 5/2!!! 9/2 has +0.728 equity, versus +0.792 for 7/2, 5/2, a difference of -0.064 and so another blunder! Extreme gammon agrees again.

The key here is the cube. With the cube in the middle, the moves I actually made are the correct moves. But the cube has already been offered and taken, and that makes a difference. I no longer have the option to double red out after a rough roll, I have to take what I get – and if I get something bad red has the redouble.

As it happens, what I got was a 5-6 on the first roll bearing in against the men still on my one point, forcing me to leave two blots. Red rolled a 5, putting me on the bar, I danced, and then got redoubled out. So it really could have worked out better for me. But the main thing was these back-to-back positions where the difference in correct play depends so much on the cube position.

This table shows the winning chances for each move for the first position, per GnuBG:

Win W g W bg Lose L g L bg
11/7, 10/7 0.811 0.129 0.005 0.189 0.005 0.000
10/6, 9/6 0.835 0.146 0.005 0.165 0.005 0.000

And this is the equity, depending on who owns the cube:

Equity Cube in Middle Equity, Red’s cube Equity, Black’s cube
11/7, 10/7 +1.000 +0.715 +1.000
10/6, 9/6 +0.934 +0.788 +0.978
Difference +0.066 -0.073 +0.022

Very similar charts for the second position:

Win W g W bg Lose L g L bg
9/2 0.824 0.115 0.004 0.176 0.005 0.000
7/4, 7/3 0.833 0.145 0.006 0.167 0.005 0.000
Equity Cube in Middle Equity, Red’s cube Equity, Black’s cube
9/2 +1.000 +0.728 +1.000
7/4, 7/3 +0.925 +0.781 +0.970
Difference +0.075 -0.053 +0.030

I find it also interesting that the drop in equity for leaving an indirect shot is a lot lower when black owns the cube in both positions as well. I think either of these would make a good “quiz” question for Phil Simborg. Having them back to back like that in a game definitely made me stop and think about the value of owning the cube!


June 18th Backgammon Tournament Results

We had an incredible turnout at Occidental Brewing this afternoon – 20 players! That is, in fact, a new record. There were a lot of newcomers or people returning after a long absence as well – I think 7 or 8 people I had not had the pleasure of meeting before.

We caught the management off guard – I should have scoped out the location earlier and I would have learned that they were a little on the smaller size, in the area we took over. Probably should have given them a head’s up, but Sara and others smoothed some feathers with the staff and once we got running, it went very smoothly. If we go there again, we’ll warn them, and probably move to the upstairs space, which is (I’m told) a little larger (I never made it up there today). Martin assured me that this is the best brewery in Portland, even though it is somewhat out of the way for people, based on the majority of comments I got.

Being such a large group, I divided us up into two brackets. You would think 20/2 = 10, but with the chaos of filling in the brackets as a few stragglers rolled in, we ended up with 9 in the A bracket and 11 in the B bracket. Oh well!

The “A” bracket ended up in a newcomers show-down. Karen beat out William for 1st, and Billy won the consolation bracket. The “B” bracket went to the established crew, with Nick beating out Gints for the big prize. I squeaked out a win in the consolation bracket, mainly because Mark F left “early” – I would have had to face him again, but he didn’t want to stick around another half hour or so for the $10 entry refund that went to third place. So: payday!

Greg made the suggestion that the consolation bracket should run 3 point matches instead of 5 point matches, in order to wrap up a little faster. By definition the consolation bracket starts later, and so it was running long. Thanks for the suggestion, Greg, we will definitely do that next time!

The other big thank you goes to my daughter, Kira, who took over the clipboard while I played and helped keep the tournaments running smoothly. What a great Father’s Day gift, eh?

All in all, we did manage to finish the tournament by 6, although Nick and Bryan were observed playing a money game as I headed out. Some people never get enough, I suppose. If you want more, we’ll do it again next month at Great Notion, on July 16th. I’ll call and warn them first!

Player Initial Elo Rating Matches Played Matches Won Final Elo Rating
Mark F 1542.6 4 4 1604.62
Karen 1500.0 4 4 1568.85
Nick 1500.0 3 3 1554.27
Billy 1500.0 4 3 1530.34
Bryan 1544.6 3 1 1523.25
Mark 1534.4 3 1 1518.88
WIlliam 1500.0 3 2 1517.10
Joel 1500.0 3 2 1513.56
Noah 1500.0 3 2 1513.53
Mally 1500.0 4 2 1506.43
Greg 1500.0 4 2 1500.15
Paul 1508.5 3 1 1492.50
Gints 1469.3 3 2 1491.31
Karla 1500.0 3 1 1483.08
Martin 1500.0 2 0 1468.08
Donnelle 1500.0 2 0 1466.07
Kristin 1500.0 2 0 1465.10
Julie 1502.8 3 0 1452.32
Sara 1482.1 2 0 1450.28
Justin 1480.7 2 0 1445.35

June 10, 2017 Chouette Results

We had a record turnout for the Chouette this month – 9 people! I was hoping we would break into double digits, but maybe next month. Mark F, fresh off his second place finish in the Chicago Open Master’s, was feeling peppy going in, and he was in charge of the “advanced” board. He asked me not to mention how he did, you can draw your own conclusions there. Julie took over the “beginner” board, where she held the box for a long, long time against newcomers Tanya and Ted. They had a lively time with lots of discussion about the best moves at each point. That left Gints and I on the “middle” board, which, if you count carefully, does not equal a chouette. But we had fun anyway.

Gints and I are pretty evenly matched at backgammon, and we ended up taking pictures of a LOT of positions for later analysis. The ones I took, I have to say, most of them were not that close – I was offering doubles much too early and accepting them much too late. But occasionally, they were interesting, as in the following:


Here I’m red, Gints is white, I have two on the bar and am being redoubled. Would you have offered that double? Would you take in my place?

The race is actually pretty even, he’s up 132 to 143. My risk is, nothing is especially holding him back at this point. He has 4 and 6 to hit my blot in the outfield, worst case scenario is bring the back checker around. Seems like a pass to me, and it is. In fact, it is too good to redouble! Winning chance is at 76%, but 44% is gammons. GnuBG says no double has equity +1.117, XG says +1.141. I’m about to get buried here, and I took the chance to drop. If you don’t think about the gammon chances, it seems like a close call, but the majority of the losses are gammons, and since the cube has already been turned, they count.

Anyway, a good time all around – we’ll do it again next month!


June/July 2017 Calendar

We’ve got the next few Chouettes & Tournaments on the calendar – check it out:

Chouettes will be on the second Saturday of each month through August – so June 10th, July 8th, and August 12th. They will all be at Lucky Labs on Hawthorne – that’s 915 SE Hawthorne Blvd if you want the actual address. Turnout has been pretty consistent so far, I hope we will build it up to be able to consistently have two tables going by the fall. Play starts at 1:00 and goes until 5:00 or so, depending on when people fall out.

We will have the June tournament on the 18th at Occidental Brewing, 6635 North Baltimore Avenue, starting at 1:00. Format to be determined – I’m thinking we’ll probably go back to a single double elimination bracket unless the turnout is pushing 16. Last time around, we moved it up to 5 point matches, and no-one complained, so we will likely do that again.

For July, the tournament will be on the 16th at Great Notion, 2204 NE Alberta St #101, again starting at 1:00. Same caveats as for June. Have you noticed a theme of North Portland based venues? I figure we will keep moving each month until someplace just screams to be the new “permanent” home.

See you there!


May 21, 2017 Tournament Results

We had a pretty decent turnout for a warm afternoon. It helps that there was sunshine yesterday as well. There was a certain amount of confusion as to which Lucky Lab was the right one, but eventually 10 people showed up.

We played one bracket, single elimination, and one round robin tournament. It almost sort of worked. I wonder if a double elimination wouldn’t have been better, but what’s done is done. If there had been more people or 2 fewer, I think the bracket would have been a little smoother. But live and learn – best alternative.

Bryan walked away with the win in the main bracket, with newcomer Courtney taking second place. Hopefully we’ll see her and Justin again next time as well – a little bit of beginner’s luck to keep people coming back and all that. In the round robin, Paul and Martin ended up tying with 12 games each, and so split the prize there, minimal though it was.

I ended up playing Gints twice – once in the bracket and once in the round robin. At one point he took a picture of a position to evaluate later, and if he sends that along I will update this post with it. In our first match, he had sent quite a few of my checkers back, and I was starting to give up hope that I would get a return hit. But I had a relatively strong board, and eventually the opportunity did arise. A roll or two later, we got to the following position, and I offered him a double:


I’m showing it here from my side of the board – Gints is red, facing the cube. What’s the play? I’ll tell you it was a good double, and I knew it right away because he had to stop and think for a bit. Evaluation from both GnuBG and XG say it’s a double. I’m up 61 pips in the race, and likely to get a better position with my next roll. But I do have 3 men back, and no outfield coverage. As it happened, Gints took, and that is the correct action – barely (for me). XG says if my checker on 23 was on 24 instead, that this is a no double/take position. In fact, I managed to pull off my 30% gammon chance, which took us from 1-each to me winning the match. But Gints was right to take, and so that’s the important thing.

In my last game with Paul, we got to the following position, with him leading 3 to 2 in our match to 5.


In the game, I redoubled. Risky play, or sensible? Paul took – smart, or overly optimistic?

Now, here the round robin tournament rules come into the decision. Martin had 10 games, Paul and I each had 6. In order to beat Martin, it was necessary both that one of us get to 6 games (most allowed is 1 over the match length), and that Martin win at most 1 in his last match. So, although this is a proper redouble, it would normally be a pass; but Paul took it on the chance that one of us would end the match with 6 games. And so it happened – I couldn’t cover the 4-spot, and was still pulling my back checkers around when Paul came back in, hit me on the way, and went on to recover the game. Meanwhile, Gints was playing spoiler, beating Martin 6-2 in their match – putting Paul and Martin tied. Overall tournament results on player rankings are as follows:

Player Initial Elo Rating Matches Played Matches Won Final Elo Rating
Bryan 1492.7 3 3 1544.62
Mark 1556.2 5 2 1534.45
Paul 1471.7 4 3 1508.49
Julie 1516.5 1 0 1502.82
Courtney 1500.0 3 2 1500.48
Martin 1600.0 5 3 1500.00
Sara 1500.0 1 0 1482.11
Justin 1500.0 1 0 1480.66
Jarom 1488.7 1 0 1471.04
Gints 1500.0 4 1 1469.33

Overall, I believe a good time was had by all. We’ll try another location next month, when we go back to the actual second Sunday of the month on June 10th – maybe somewhere with a good happy hour. See you there!


April 22, 2017 Chouette Results

We had a great turnout for today’s Chouette – 9 people total. Mark F kept order on the “Advanced” board, where 5 brave souls played for $10/point; while I (mostly) played with 3 others on the “Beginner’s” board at $0.50/point. I say “mostly”, because I did get in about 4 games on the “Advanced” board, both before and after the “Beginner’s” board ran. Martin, Mark S, and Bryan were all still going when I left at 6:30, too!

The action was hot on the “Advanced” board, of course, with Martin coming out well ahead but decent showings for a few others as well. Martin and Bryan are both off to Vegas later this week for the US Open, and so we all wish them good luck.

The “Beginner’s” board was far more relaxed – couple of times people took a double that was probably a technical pass in an attempt to get the box. I had a good run as the box at the outset, which left me well up through the later rotation. Michael provided the board for the first bit, then we switched to Julie’s board when he needed to head out. Paul made his return appearance and I can assure you he hasn’t gotten rusty while he was traveling – he walked away with $0.50 in winnings!

Here’s one position we ended up arguing about for a good little while. At the “Beginner’s” table, we had full consultation at all times, including occasionally the box helping the field or vice versa… Anyway, the argument was, do you come out or do you stay on the opponent’s 4 point?



Julie was the captain, and wanted to come out past the bar. Paul and I were not so sure, and thought staying in provided more chance of a hit. Julie went with the escape, and good thing – staying back is a blunder! Black is not in good shape, but has 31% winning chance if he comes out, only 16% chance if he stays back.

Later, in the following position, I offered Julie the cube. Good move? Would you take?


I figured that I needed 5’s to get out, there’s a decent chance that won’t happen, and so this looks like a double/take. Julie disagreed, and dropped. Well, I was off! My winning chances are about 73% according to GnuBG, but my gammon chances are 41%, making this position too good to double! I clearly need to work on my probability estimates. Then again, with the Jacoby rule, it’s a proper double but still a drop. Lucky me, I wasn’t on the receiving side of that cube decision.

We’ll be back at Lucky Lab for a chouette next month, probably earlier in the month, as the second Sunday tournament will be moving to the third Sunday to not conflict with Mother’s Day, and then following that is Memorial Day. So yeah, the schedule will shift a bit. See you then!



April 9 2017 Tournament Results

We had 13 people show for what is (most likely) our last meetup at Circa 33… Because some people have asked, my reasons for making a change are largely due to the original reasons for us having it there:

  1. It’s close to Rob’s house [well, he’s not hosting anymore, so…]
  2. They had an all day happy hour [well, now it starts at 4, so…]

We got a couple of good suggestions for a new location, so I will go on a pub crawl over the next weeks and pick one. If it doesn’t work out, I’m not afraid to move it again!

We experimented with a new format too. The fun thing about experiments is that sometimes they don’t work. It was far from a disaster, but it could have gone better. With 13 people, we had not quite enough people for two 8-person brackets, and so naturally I tried to run three brackets! That was also a function of trying to have both a $5 and a $10 entry. Then the side pool question got confusing for people… Well.

By 3:10, I had 7 people signed up for the $10 bracket, so I got that kicked off. 3 people opted for the $5 bracket. Then newcomer George arrived. I wanted to put him in the $5 bracket, as a newcomer, but he insisted that he wanted to play the $10. So that filled the $10. Turns out, George is a professional poker player and no slouch at backgammon – more on that in a bit.

Mark F and Bryan both arrived before 3:30, and I promised them a second $10 bracket. Here’s where my planning fell apart. A few months back, when I visited the weekly tournament in Vegas, they run it on a strict 8 person bracket, once you’re out you have to buy-in to a new bracket. I was thinking people would do the same, but I wasn’t considering that I was using a double-elimination structure still, which meant that no-one was finishing up to enter the third bracket. So Mark & Bryan ended up just playing heads-up. Sorry guys!

In the $5 bracket, Julie trounced newcomers Bob and Aaron, although knowing Julie, she was very nice about it.

In the $10 bracket, Kevin repeated his undefeated approach from last month.

Now let me whine for a moment. My first game was against Sharon, and it was a good match – lots of ups, lots of downs. I barely squeaked by, then sat down to play Larry. It was a good match again: I won, he won a double, I got through the Crawford game, and then was cruising towards a crushing victory in the double-match game. I had him trapped behind my prime, his board was crashed, put him on the bar, started bearing off – clearly victory was mine. Until I was forced to leave a blot, and Larry hit it. Well, that happens, and I had a huge edge, came in immediately, just needed to get around the board and… Larry rolled double 6’s. So now he was bearing off while I was still getting around the board, but no big deal, I had some big rolls, and soon enough we were sitting with me having 5 checkers to bear off and him having 12. Now, he was on roll, but no big deal, the only way he could win was to roll doubles – 3 times in a row. Which he proceeded to do. 1 in 216 odds, I lost the match!

Well, I went down to the consolation bracket to play George, who told me he plays mainly on Gridgammon, and has spent a decent amount of time playing Victor Ashkenazi. Playing online against giants does tend to hone your skills, and so George took me out too, though I think I gave him a decent run for it.

George ended up winning the consolation bracket, which got him his entry fee back, but not his side pool bet. I had declared that the winner of the side pool got it all, and that ended up being Larry. Talk about a lucky guy! Larry placed second, losing to Kevin in the final, but Kevin had not entered the side pool! So Kevin got the winnings for the tournament, but Larry got about twice that for the second place plus the side pool!

Again, a learning experience for me. With the shorter tournament structure, I think next time we’ll do 8 person, single elimination brackets, and if you want to keep going you can buy into a new bracket – Vegas style.

So next month, aside from the venue and the format, it’ll be about the same. Also, in response to Tim’s lobbying, the tournament will start earlier in the day – noon or 1, I think. But other than that, about the same. See you there!


Player Initial Elo Rating Matches Played Matches Won Final Elo Rating
Kevin 1543.5 3 3 1584.64
Mark 1578.7 3 1 1556.23
Mark F 1529.7 1 1 1542.59
Dick 1541.4 4 2 1534.14
George 1500.0 4 3 1532.47
Tim 1546.3 2 0 1517.23
Julie 1488.4 2 2 1516.49
Larry 1494.1 3 2 1512.44
Bryan 1505.6 1 0 1492.71
Sharon 1511.4 2 0 1487.40
Aaron 1500.0 1 0 1486.25
Bob 1500.0 1 0 1485.68
Emerald 1471.8 3 1 1464.38

March 12, 2017 Tournament Results

I learned two very important lessons today.

  1. If you have 17 people show up for a tournament, there is no reasonable way to get them done in just 3 hours. Break it into a couple of brackets?
  2. When you print out a 17 person bracket, make sure the font on the numbers is large enough to read, or you are going to screw up some of the moves to the consolation bracket!

Let me spell out the impact of the logistical challenges – at one point I put someone into the wrong line, which meant when the next person moved down, there was already a match happening there, which meant that there was a cascade effect. The worst impact of which was that I ended up playing Mark F twice, and got eliminated. Sad!

Nevertheless, I did give him a pretty good run. Here’s a position that came up in our second match, when we were 1 each in the 3 point match.

Here I’m black and Mark is red. I offered the cube. Good move? Take or a drop?

My probability of winning is about 70% according to GnuBG. If it were a 0-0 score, this would be a take. But given that the match results would depend on it, it is a pass. Mark correctly dropped, then gammoned me in the next game. Smart move, eh?

The group was a good mix of new people and returning players, with a couple of folks who hadn’t been around in quite a while – looking at you, Ed. Most people went for the side pools, and so the first place ended up being worth over $100 – $125 I think. Second went home with $60, third got their ante back. Ed took third. Newcomer Kevin and returning player Dick were in the running for 1st/2nd, but Dick made a concession to the logistics of their respective drives and conceded – they’d already played once, which was how Dick had got started in the consolation bracket. ANYWAY, Dick and Tim had a drive back to Astoria, and Kevin and Sharon had a drive back to Coos Bay (!!!!), and it was 7:30 and my wife was texting to ask if I’d died in a car wreck on the way home. So, that was that.

In spite of the anticlimax of the ending, it was a heck of a day of backgammon. Hope you’ll make it back next month, when I promise to do something different to make it run more quicker.

Here’s the ratings going into/out of tonight. See you next month!

Player Initial Elo Rating Matches Played Matches Won Final Elo Rating
Bryan 1486.2 6 4 1505.61
Dick 1500.0 6 5 1541.41
Ed 1500.0 5 3 1518.88
Emerald 1500.0 2 0 1471.76
Jarom 1513.0 2 0 1488.73
Julie 1485.0 4 2 1488.42
Kevin 1500.0 4 4 1543.48
Kirstin 1500.0 3 1 1493.10
Larry 1500.0 3 1 1494.13
Mark 1600.7 3 1 1578.71
Mark F 1500.0 6 4 1529.69
Matt 1500.0 3 1 1493.67
Michael 1500.0 3 1 1532.10
Paul 1500.0 2 0 1471.71
Sharon 1500.0 4 2 1511.45
Tim 1553.2 4 2 1546.33
Trish 1476.6 2 0 1454.43

February 18, 2017 Chouette Results

Turns out, it was zwikelmania on the 18th. As a result, Lucky Lab was very crowded. I showed up a bit before 1:00, and set up next to the front door. Before 1:00, a group of people started playing darts right behind that table. There was a lot of traffic, but not obviously anyone looking for backgammon. After a while, I went and walked through the bigger room, and found Dan, who had been sitting around waiting for someone else to show up too. We moved back to the front table and played a money game for an hour or so, took a break for Dan to deal with a little work, then settled in for a chouette with the arrival of Rob and Martin about 3:00.

Well, I was already way down due to Dan’s excellent dice throwing skills, and the arrival of backup just meant that someone else got to lose with me. Dan held the box for two full cycles at one point, making bank off us. Still, I had fun, and we even had a random stop-by pick up one of the postcards: Mel, who learned to play in Turkey, and who challenged me to a couple of just for fun games.

At one point, playing against Dan, I faced the following decision:

That’s the doubling cube being offered to me. Now here’s where psychology comes into the game. Mathematically, this is a no double and an easy take. But we were in the 5th game or so in a row where Dan had whipped me. 1’s, 2’s, 3’s, and 4’s hit, 5’s and 6’s escape a back checker. And I hadn’t had a good roll, nor Dan a bad one, so far this game. In spite of his odds being only 0.567 (according to gnuBG), I passed.

Let me tell you, failure of confidence can get expensive.

We’ll be back next month – maybe a few more new people will show up to take some of my money off me. Hope to see you there!