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Simple Overview of Ratings ( PPI)The purpose behind the Past Performance Indicator ( was called "ratings") scheme is to produce a figure based upon your recent results, which are expressed as a percentage, and you may look up your own figure on your own profile. Most bridge players like to see their scores and how they did. Our P.P.I. scheme is designed to give a broad and reasonable way of allowing members to monitor how they are doing on a day by day or month by month basis. The other key aspect about the P.P.I. scheme is that it is useful to know roughly the standard of the bridge players you are partnering and opposing. Games involving partners of very different standards tend to be very uneven and less enjoyable – an inexperienced player partnering a Grand Master may feel extra pressure, while a Grand Master may find it tedious to see partner make elementary plays. Similarly, two top players playing against two beginners may provide an uneven match. Other members looking at your profile (and vice versa) may see one
of four symbols PPT's should be used as a guide only and not taken too seriously. How it worksThe formula calculates a P.P.I. figure for each player and these figures, which are expressed in the form of percentages, could be described as handicaps, and they are used as handicaps or as the basis for seeding in a small number of Bridge Club Live’s Special Competitions. Our scheme is considered to be one of the best of those used by Internet Bridge Clubs or, for that matter, anywhere else. The P.P.I. figures represent the percentage scores that a player would expect to average if partnering another player with the same P.P.I. against a given field (ie the online club membership). Your P.P.I. figure is updated after every event in which you play in any rooms except the Social and Coaching Bridge Rooms, the Special Competitions Rooms and any room with IMP scoring. The update takes place as the event is archived. (A similar system could work for Butler competitions, though there are no plans for such at the present time.) The calculations take your partners’ and your opponents' P.P.I.s into account as well as how many boards you play in each event. The range of PPI figuresThere are no artificial limits to the P.P.I. figures. The strongest players have P.P.I. figures of 60% or more and intermediate players could have figures of less than 40%, a difference of 20%. The spread of P.P.I. figures for players tends to form a Normal Distribution with the obvious mean of around 50% and with a Standard Deviation of around 5%. What this means is that about 68%, over two thirds, of all members will have a P.P.I. between 45% and 55% and about one sixth will have a P.P.I. above 55% and about one sixth will have a P.P.I. below 45%. Two and a quarter percent of all members will have a P.P.I. above a figure of around 60%. Bridge Club Live displays P.P.I.s of members by way of one of four suit symbols on the profile of each member. This method was deemed the most popular in a referendum of members in 2005.
Having selected these bands, it will therefore be found that :
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