There is a new backgammon league starting up in Ottawa. All levels welcome! See below. Ottawa Area Backgammon – Weekly Tournaments March 12, 2017 Dates: Every Wednesday evening starting March 22, 7:00 PM Venue: Busters Bar & Grill Lincoln Fields Shopping Centre, 2525 Carling Ave, Ottawa, ON K2B 7Z2 Match Length: 5 points Entry Fees: $20 entry fee with optional $20 side pool Prize Distribution: Entry Fees: 1 st – 50%, 2nd – 25%, Consolation Winner – 25% Side Pool: Farthest in Main Bracket – two thirds (2/3), Farthest in Consolation Bracket – one third (1/3) Club Points: 1 point for each win. (no points for a bye.) Additional (Bonus) Points for placing in the tournament – 4 points for winning the tournament, 2 points for coming in 2nd or winning the Consolation. Tournament Directors: Stuart Thomson – Cell: (613) 413-4234 Eden Windish Statistician: Scott Douglas Everyone is guaranteed 2 matches. Please note that the Holland rule will not be in use for these tournaments. The tournament draw will start at 7:00pm sharp. If you think you will be a little later than 7:00pm, please call my cell ahead of time so we can place you in the draw. Also, it will help the club’s reputation greatly if everyone can order some food or drinks. Ultimately the restaurant needs patrons that spend money and this includes us!

This position came up and someone wanted to know why it was such a big double for red. Here's 3 responses from 3 separate members of the Ottawa BG club. Feel free to leave your opinion. 1. "I see the effective pip count as close to even with all of blue's wastage and the gap on the 4. I don't think there is any roll for red that blue has an immediate re double? You also have to look at red's 5% gammon chances where blue has no gammon chance. When red does hit, his winning chances are over 90%. When red rolls a missing number like say 5-2, he can play 13-6 with not much worry and blue doubling after that would be a big blunder. I see this as a pretty big edge for red." 2. "First of all the idea of an immediate redouble is insignificant since the cube is centered and would have been available to blue anyway. The pip count is deceptive, red has a perfectly smooth bear off. It’s better to count crossovers in the outfield and the pip count in the outfield. The crossovers are 6 to 5, with red on the roll. The outfield pip count is 26 to 29. Also, when red fails to throw a 6, he can still move off the 13 point, say with a 54, if he wants since blue’s board is not set up to contain a man on the bar. It’s a double because any hit is a loss of market. This type of position occurs often, the important thing is to know that it is a take for blue." 3. "I set up the position on gnu, and it also considers it a definite double--I would guess because of the blot in blue's home board which must involve a real gammon risk in case red hits and gets hit in return. But even when I moved that blot to the 22 point, gnu still thought it is a double, but a very borderline one."

This, of course, is what all the fighting is about. The Lessard Cup! The best record over the course of a year takes her home.

Here is the website for the Ottawa Backgammon Club: http://leaderdragon.tripod.com/bgammon.html Tournaments take place at 9:45 on the first Sunday of every month (except July and August)at Buster's Bar and Grill at Lincoln Heights Shopping Centre, 665 Richmond Road. All are welcome. You should be there at 9:30am if you want to play. Buy-in is low.

Interesting BG book

www.bkgm.com/books/Euler-EverydayErrorsInCheckerPlay.pdf
Here's a mysterious Backgammon Book that appeared on the internet awhile back.

I haven't posted for a while, remember, the next time the Ottawa Backgammon Club meets is September 7th, 2014 at Buster's Bar and Grill, 2525 Carling Avenue at 9:45 in the morning.

We take the Summer off.


Enjoy the book!

Here's a position I ran across which I should have known.
I think it needs to be posted so no one else gets hypnotised by the big cube and drops.

The comments are from Bruce from the club.
(black to roll)

here's the rollout from ExtremeGammon.

65.51% wins for me 34.49% for you. Should have been no double/take. 0.029 error on my part to offer.

I still think it's a good pressure double two times out of three I would have gone 6-3 up.......

If all the checkers were on the one point it would be 75.43% wins for me and 25.47% for you. So three times out of four I would have been 6-3 up and Extreme Gammon still calls that a double/take and a 0.165 error if you dropped. Not convinced about the bot's reasoning sometimes...... too mathematical maybe - maybe reducing it to outcomes is not such a bad approach in these instances as a guide for decision-making.

 

 

 

 

This interesting position occurred. Black doubled and white took a good 10 minutes to decide, even though there seems to be symmetry, his position is about to collapse. (Note, the bottom of the picture is white's inner board.) The best white could hope for was to be hit and fail to enter, or have black break even faster than him. Not very appealing.

A member with a bot analysed the position and wrote this:

"At a 2-to-3 score up to 9, Black the trailer should double and White the leader should drop.  It is a substantial blunder to take, about 1/8 th point per normalized game.  Both the XG evaluation player and a moderate number of  live cube rollouts (2500) agree on this equity difference."