Saturday, August 25, 2007

backgammon – the rules

Below is the hardest part of the backgammon rules – at least to me. The starting position:



Backgammon is one of those games you can learn within a couple of minutes but need a lifetime to master. But no matter how good – or bad - you are it is a very addictive game.

Each player has 15 checkers and two dice. The object is to run around the board with all checkers and “bear off” – move them off the board. The player who first removes all his stones wins.
After the board is set up each player rolls one dice. The higher roll starts the game – roll again after a draw. This first roll is also used for the first move. The starting player uses his roll and his opponent roll to move his checkers – later each player rolls both of his dice.

The numbers on both dice can be split to move two checkers or the whole roll can be used on one checker - to use the combined roll two moves using the different numbers must be possible. It is just like making two moves with the same checker. In backgammon like chess each player has to move – even if he does not like to. He has to use his whole roll if there is a legal move to do so.
Throwing the same number with both dice is called a double. Allowing to move this number not only twice but four times.

The red stones – in the above example – run from the lower right to the upper right – their home board. The black stones move in the opposite direction to their home board on the lower right.

A single checker – also called blot – can be hit by the enemy by moving to the same field. When a stone is hit it returns to the bar in the middle of the board. If a player has a checker on the bar his first play after rolling the dice must be to return the checker into the game – according to his dice he has to enter into the enemies home board (black onto the fields 1-6 and red onto the fields 19-24 [see picture above]). If he can not legally enter the checker back into the game his move is forfeit and his turn is over. After entering the board he can use the rest of his roll how he wants to.

As soon as a field is occupied by two or more checkers – called a point – the opposite player can not move to this field. It is blocked. Several points in a row are a prime. As soon as a player build a 6 point prime or full prime – 6 points in a row – the other player can not cross this barrier because the highest number on a dice is the 6. So there is no legal move to jump over these points – until the other player has to move his checkers again. If a player has build a full prime in his home board – a closed board - and the other player has a checker on the bar he does not even have to roll a dice because he will not be able to make a legal move.

As soon as a player has all his checkers inside his home board he can start to bear off. If his numbers on the dice are higher then any legal move on the board he can use it to bear off the checkers most far away.

Example:
Red has two checkers on the 5-point and one each on the 3-point and 2-point. He rolls 6 and 3. He can use the 3 to bear off the checker on the 3-point and the 6 to remove his checker currently on the 5-point.

The player bearing off all of his checkers wins. If his opponent did get at least one checker of the board himself it is called a single gammon – worth one point. If that is not the case he wins a gammon or double game – worth two points. It is called a backgammon or triple game – worth 3 points; surprise – if your opponent has still a checker on the bar or your home board.
Now get GNU backgammon and start a game...

Sunday, August 12, 2007

poker is fun - no it is not

well i have to make another post about poker. just to show you want a perfect week party poker gave me.

the graph is made by PokerEV (a software that displays your luck - well it shows how much money you won and how much you should have won statistically aka in the long run). the red line shows how much money i should have made...it shows a small but decent plus. the blue line is the winnings whenever i got to a showdown and the green line shows my actual winnings or to be correct my losings in the last few days :(
and is you can see by the large gap between the lines i am running bad as hell.
sorry for writing a "poker blog" post but i just needed to tell everyone how unlucky i am.

Sunday, August 5, 2007

get your personal chess trainer

Well the best way to learn and master chess is to have your own personal trainer like an IM or even a GM. Another good option is to use a program called personal chess trainer. It offers hundreds and thousands of exercises within 3 different categories (tactics, endgames and strategy). After a couple of exercises there is a repetition to check and deepen what you have learned. It really helps to train your ability to identify certain patterns on the board and how to exploit these situations.
The free trial of the software lets you exercise 5 units of each category. You should really give it a try and see how it helps your chess.

Friday, August 3, 2007

queens in trouble - an interesting poker hand

I found the following hand on the internet and i think it is a really interesting. There is no additional information on the other players involved. Well they all limped in so i guess there are not really playing a TAG (tight aggressive) style.

Preflop: Hero is Button with QClub, QHeart.

UTG calls, 2 folds, MP2 calls, MP3 calls, CO checks, Hero raises, 2 folds, UTG calls, MP2 calls, MP3 calls, CO calls.


Flop: (11.40 SB) THeart , JHeart , QSpade (5 players)

Now that is a good flop – dangerous but good. Right now we got top set – a very strong hand – only 3 hands are beating us right now (AK, K9, 98). AK would have raised before the flop. So K9 and 98 are the only hands we have to fear. And even against these straights we have a couple of outs (cards that would give us the better hand) because we can still make a full house. Pokerstove - a program to calculate your chance to win a hand – says QQ is a 53% favorite to take the pot (assuming all opponents are limping with the top 30% of their hands and raising 10%). I think that range is pretty good for these enemies. Actually i think they will limp even more – given us a better chance to win.


UTG bets, MP2 calls, MP3 folds, CO calls, Hero raises, UTG calls, MP2 calls, CO calls.

The first player bets and everyone else calls. We have to raise here. Most likely the set is the best hand and we have to charge all players drawing for a flush or a straight. Maybe UTG has us beaten right now but we have outs and let the others pay if they are still drawing. Once again the queens have a 53% chance to win this hand. As soon as our chance is bigger than 20% (because there are 5 players) it wins money in the long run to put more chips into the middle.


Turn: (9.70 BB) 8Diamond (4 players)

The 8 is a bad card for our queens. Now every 9 makes a straight already. Pokerstove still shows 32% to take the pot. We are still a favorite against the range of our opponents.


UTG checks, MP2 checks, CO bets, Hero....

Now we have to make a tough decision. The player in the cut-off wakes up and bets into us. We have to assume that the 8 helped him – he made the straight. If we believe he has the 9 and the range for all other players stays the same our chance to win drops to 20%. So that is really on the edge. I would love to raise and kick out the flush draws. But raising would give the following players still the needed odds to draw because they have to pay 2 BB for a pot of 12.7 BB and there are 9 cards of the remaining 46 cards giving them the flush. So raising will build a bigger pot for the guy with the straight and knocking out other draws or made hands would reduce the equity of our hand. Reducing the amount of players while building the pot with just a 20% chance to win will lose money in the long run. So calling is right. Remember we still have a draw ourselves to win the hand. And flat calling will invite others to call. So maybe some two pairs will stay in and give us additional money if we hit our full house - besides the flush draws.

Hero calls, UTG calls, MP2 calls.

River: (13.70 BB) AHeart (4 players)

UTG bets, MP2 calls, CO calls, Hero folds.

The ace of hearts is maybe the worst river card we could expect. We did not improve our set to a full house. And in addition now every king makes a straight and the flush draw hit. Now the player first to act bets into the whole field. He really has to have a hand. I would say he was drawing for a flush and finally made it. He bet out on the flop with his flush draw to build a big pot. He called the turn so most likely he did not have a straight then. Well even if he did not complete a flush he is telling the table that he has a strong hand and there are two callers in front of us. There are to many ways we are beaten so we just fold our lovely three ladies.

If you think that the analysis is wrong and you would play the hand different feel free to leave a comment.