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Login: | Explaining level changesAlistair Johnson v Tim O'Leary (Wed 19 Jun 2024)Match won by Alistair Johnson. Result: 15-6,15-6,15-11.Starting level for Alistair Johnson: 596, level confidence: 62%. Starting level for Tim O'Leary: 654, level confidence: 61%. Tim O'Leary to win as he is currently playing 10% better than Alistair Johnson. Alistair Johnson won all of the games and 66% 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 96% (PAR scoring). These are weighted and combined to calculate that Alistair Johnson played 96% better than Tim O'Leary in this match. Assuming that any level changes are shared between both players, for this result it looks like Alistair Johnson actually played at a level of 873 and Tim O'Leary at a level of 446. Without any damping, both players would need to be adjusted by 47% 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 Alistair Johnson changes to +44% and Tim O'Leary changes to -44%. After applying standard match damping, the adjustment for Alistair Johnson becomes +21.7% and for Tim O'Leary becomes -22%. Apply match/event weighting of 50% for 'Redland Green Boxes' so the adjustment for Alistair Johnson is +10.9% and for Tim O'Leary is -9.8%. 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 Alistair Johnson is limited to +10% and Tim O'Leary 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. Alistair Johnson: 78%, Tim O'Leary: 78%. Reduce level confidence based on how unexpected the result is. Alistair Johnson: 54%, Tim O'Leary: 53%. A final adjustment of -0.1% 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 Alistair Johnson: 655, level confidence: 54%. Final level for Tim O'Leary: 623, level confidence: 53%. Notes
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