Something to stretch your mind ! Please translate male gender references into female if you wish


The concept is that player strengths are distributed, in statistical terms, normally that is to say most players are grouped around an average strength and there are only a few very good or very bad players. In a large group of players there are an equal number of better-than-average as there are players weaker-than-average. If we charted the number of players from worst to best we would get a bell shaped curve representing their distribution most of them about middle strength. This particular curve the Normal Distribution is a very common characteristic in nature and follows a specific formula for its shape. It also indicates the probability of an event happening.

PRINCIPLES - Each player has a RATING. The RATING is a measure of his strength. The difference between two players' RATINGS is indicative of the probability of the higher rated player winning.

A difference of 100 points implies a 66% probability of a win.

The spectrum of points runs from about 1500 (lower end of league) to 2800 points (premier league). Currently the top four men in the world have a rating of about 4000.

How does the rating change? The outcome of the match and the points difference between the two the players determines how many points are awarded to the winner and how many are lost by the loser. What the one player gains the other player loses.

If each player has the same rating to start with then the winner will gain 50 points and the loser loses 50 points.
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