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Login: | Explaining level changesDivision 3: University of Bath 4 v BAWA / Kingswood (Wed 28 Feb 2018)Match played between Ben Merritt (home) and Piers Fleming (away).Match won by Piers Fleming. Result: 4-9,7-9,7-9. Starting level for Ben Merritt: 1,397, level confidence: 63%. Starting level for Piers Fleming: 1,249, level confidence: 70%. Ben Merritt to win as he is currently playing 12% better than Piers Fleming. Piers Fleming won all of the games and 60% of the points. This games result would be expected if he was better by around 55% or more. This points result would be expected if he was better by around 24% (english scoring). These are weighted and combined to calculate that Piers Fleming played 34% better than Ben Merritt in this match. Assuming that any level changes are shared between both players, for this result it looks like Piers Fleming actually played at a level of 1,530 and Ben Merritt at a level of 1,140. Without any damping, both players would need to be adjusted by 23% to match this result. Factoring in the relative levels of confidence which allows players with low confidence in their levels to change more quickly, the adjustment for Piers Fleming changes to +19% and Ben Merritt changes to -21%. After applying standard match damping, the adjustment for Piers Fleming becomes +9.8% and for Ben Merritt becomes -10.2%. Apply match/event weighting of 75% for 'Mixed Spring 2017/2018' so the adjustment for Piers Fleming is +7.3% and for Ben Merritt is -7.5%. Apply limits to the amount of change for a single match which are based on player level, level confidence and time since last match so that Ben Merritt is limited to -5% level change. In general a player's level won't go up by more than 10% or drop more than 5% if they've played in the last 7 days but those limits are relaxed if their previous match was further back. Increase level confidence due to one more match played. Piers Fleming: 83%, Ben Merritt: 79%. Reduce level confidence based on how unexpected the result is. Piers Fleming: 68%, Ben Merritt: 65%. A final adjustment of -1.5% has been made to both players as part of the automatic calibration that is performed after each match. All players in this pool will have been adjusted equally in order to remain equivalent to other player pools. Final level for Ben Merritt: 1,289, level confidence: 65%. Final level for Piers Fleming: 1,342, level confidence: 68%. Notes
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