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Login: | Explaining level changesDivision 2A: BAWA / Kingswood v Westbury David Lloyd B (Wed 11 Feb 2015)Match played between Tomas Urbanovsky (home) and Vivi B (away).Match won by Tomas Urbanovsky. Result: 9-6,9-4,9-3. Starting level for Tomas Urbanovsky: 1,327, level confidence: 79%. Set manually. Starting level for Vivi B: 1,234, level confidence: 66%. Tomas Urbanovsky to win as he is currently playing 8% better than Vivi B. Tomas Urbanovsky won all of the games and 68% 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 48% (english scoring). These are weighted and combined to calculate that Tomas Urbanovsky played 50% better than Vivi B in this match. Assuming that any level changes are shared between both players, for this result it looks like Tomas Urbanovsky actually played at a level of 1,569 and Vivi B at a level of 1,044. Without any damping, both players would need to be adjusted by 18% 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 Tomas Urbanovsky changes to +15% and Vivi B changes to -18%. After applying standard match damping, the adjustment for Tomas Urbanovsky becomes +7.7% and for Vivi B becomes -9.2%. Apply match/event weighting of 75% for 'Mixed Spring 2014/2015' so the adjustment for Tomas Urbanovsky is +5.7% and for Vivi B is -6.7%. 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 Vivi B 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. Tomas Urbanovsky: 89%, Vivi B: 81%. Reduce level confidence based on how unexpected the result is. Tomas Urbanovsky: 75%, Vivi B: 69%. A final adjustment of +0.7% 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 Tomas Urbanovsky: 1,401, level confidence: 75%. Final level for Vivi B: 1,193, level confidence: 69%. Notes
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