|
Menu
Login: | Explaining level changesCecilia Mercieca v Natalie Lawrence (Sat 19 Jan 2013)Match won by Natalie Lawrence. Result: 8-11,4-11,10-11.Starting level for Cecilia Mercieca: 679, level confidence: 45%. Starting level for Natalie Lawrence: 1,776, level confidence: 62%. Natalie Lawrence to win as she is currently playing 162% better than Cecilia Mercieca. Natalie Lawrence won all of the games and 60% of the points. This games result would be expected if she was better by around 55% or more. This points result would be expected if she was better by around 50% (PAR scoring). These are weighted and combined to calculate that Natalie Lawrence played 52% better than Cecilia Mercieca in this match. Due to the difference between the players' levels, allow for the likelihood that Natalie Lawrence was taking it easy by anything up to 20%. This gives her an allowed level range for this match between 1,136 and 1,776 without affecting her level. As Natalie Lawrence has played below her allowed range at 1,082, her level reduction is 5% before damping. On the assumption that Natalie Lawrence would normally have been playing at level 1,420 (based on typical behaviour), Cecilia Mercieca played better than expected and therefore gains a pre-damping level increase of 17%. Allowing for the difference in level between the players, the adjustments have been reduced to 3.1% and 10.5% respectively. Factoring in the relative levels of confidence which allows players with low confidence in their levels to change more quickly, the adjustment for Natalie Lawrence changes to -2.2% and Cecilia Mercieca changes to +10.5%. After applying standard match damping, the adjustment for Natalie Lawrence becomes -1.8% and for Cecilia Mercieca becomes +6.7%. Apply match/event weighting of 100% for 'Avon Senior Open' so the adjustment is unchanged. Increase level confidence due to one more match played. Natalie Lawrence: 79%, Cecilia Mercieca: 67%. Reduce level confidence based on how unexpected the result is. Natalie Lawrence: 60%, Cecilia Mercieca: 51%. A final adjustment of -2.8% 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 Cecilia Mercieca: 720, level confidence: 51%. Final level for Natalie Lawrence: 1,660, level confidence: 60%. Notes
|