Thursday, January 22, 2015

Chess Graphs: Risk vs. Reward



How to play against lower rated players

I have been given conflicting advice on how to play lower rated players.  On the one hand, a strong master told me I should play the sharpest tactical opening lines, and try to blow my lower rated opponent out of the water as quickly as possible.

On the other hand, I get this advice from the book Chess for Tigers by Simon Webb.

"Do you know how Tigers catch Rabbits?  Do they rush after them and tear them limb from limb?  Or do the stalk them through the bush before finally creeping up on them when their resistance is low?"

My personal experience has lead me to believe the  2nd approach makes more sense.  When I play complicated forcing moves against my lower rated opponents, I often just put them in a position where they must find the one move that doesn't lose, and they sit there until they find it.  In effect, I am forcing them to play good moves.  When I play less forcing moves (still strong moves, just less forcing) I sometimes give my lower rated opponents more chances to make positional errors that I can exploit later.


Now for the Graphs

Imagine if I were to make a scatter plot of chess games.  On the x axis would be a measure of the risk involved in the chosen moves (I'm not sure how I would measure this, but sacrifices and gambits would be on the high end of the scale).  On the y axis would be a measure of the outcome of the games, from loss to win, perhaps measured by computer evaluations of the final positions.

That graph might look something like this:


For two equally rated players, I would expect all of the data points to fall between the two dashed lines.  Notice that when neither player takes much risk, a draw is a likely result.  As either player increases the risk, however, the chance of a win or loss increases.

Now consider games where one player is much higher rated than the other.  By much higher rated, I mean at least 200 rating points higher (you would expect the higher rated player to score 75% ).  I expect the shape of the points to be about the same, just shifted higher.


Looking at this graph, I would conclude that the higher rated player has almost no chance of losing the game if the risk level stays low.  As the risk level increases, the chances of winning increase slightly, but so do the chances of losing. 

There is a phrase used by strong players when referring to a situation where one player is controlling the risk level of the game in order to avoid a loss.  They say the player is "playing for 2 results."  Those results being a win or a draw.  If there is some risky play (a sacrifice perhaps), the player is "playing for all 3 results."


How to play against higher rated players

So if the higher rated player wants to minimize the risk involved, the opposite must be true for the lower rated player.  Looking at the graph, it appears the only chance the lower rated player has is to maximize the risk level.

Once again, I quote Simon Webb:

"The basic principle is to head for a complicated or unclear position such that neither of you has much idea what to do, and hope that he makes a serious mistake before you do.  Of course you are still more likely to lose than to win, but by increasing the randomness of the result you are giving yourself more chance of a 'lucky' win or draw."

 He then gives some pointers for increasing the risk level against higher rated players.  (I am paraphrasing):
  1. Choice of Opening -  Sharp theoretical lines and gambits.
  2. Play actively-  Aggressive attacking play, even if that means sacrificing a pawn or two.
  3. Randomize - Create unclear and unbalanced positions; complications that can't be figured out over the board.
  4. Don't swap everything off -  Strong players are better in the endgame, so keep the pieces on the board and stay in the middle game.
  5.  Be brave - Your opponent is higher rated so you have nothing to lose.

Conclusion

My tournament experience has convinced me that this is the correct advice.  Against a lower rated player, I accumulate small advantages and trade down to a winning endgame.   My games may last a long time, but I win a very high percentage of them.  Against higher rated players, I throw everything I have at them, often in a caveman like style, but I have some nice upsets as a result.

In a future post, I will show how I changed my opening repertoire to take this advice into account.





No comments:

Post a Comment