|
Wins Above Replacement or Wins Above Replacement Player, commonly abbreviated to WAR or WARP, is a non-standardized sabermetric baseball statistic developed to sum up "a player’s total contributions to his team".〔Fangraphs: WAR〕 The WAR value calculated for a player is claimed to be the number of additional wins his team has achieved above the number of expected team wins if that player was substituted by a replacement level player: a player that may be added to the team for minimal cost and effort.〔 Individual WAR values are calculated from the number and success rate of on-field actions by a player (in batting, baserunning, fielding, and pitching), with higher values reflecting larger contributions to a team's success.〔Schoenfield: 2012〕 A high WAR value built up by a player reflects successful performance, a large quantity of playing time, or both combined. For example, Fangraphs rates Clayton Kershaw's 2014 regular season performance at 7.2 WAR, suggesting his team won roughly seven more games than would be expected if his innings were pitched by a replacement level player. Kershaw achieved this high WAR total by pitching many innings while maintaining a high rate of strikeouts and low rates of home runs and walks. == Overview == The basis for a WAR value is the estimated number of runs contributed by a player through offensive actions such as batting and baserunning, and runs denied to opposition teams by the player through defensive actions like fielding and pitching. Statistics such as weighted on-base average (wOBA), ultimate zone rating (UZR), ultimate base running (UBR), and fielding-independent pitching (FIP) measure the effectiveness of a player at creating and saving runs for their team, on a per-plate appearance or per-inning basis. These statistics can be multiplied by the playing time of a player to give an estimate of the number of offensive and defensive runs contributed to their team. Additional runs contributed to a team lead to additional wins, with 10 runs estimated to be equal to roughly one win.〔http://www.fangraphs.com/blogs/win-values-explained-part-five/〕 Therefore a 1.0 WAR value for a player signifies a contribution of roughly 10 more runs than a replacement level player, over a specified period of time. A replacement level player is defined by Fangraphs as contributing 17.5 runs fewer than a player of league-average performance, over 600 plate appearances.〔http://www.fangraphs.com/library/war/war-position-players/〕 Therefore a 1.0 WAR player has contributed an estimated -7.5 runs relative to average over the same number of plate appearances, a 2.0 WAR player has contributed +2.5 runs, and a 5.0 WAR player has contributed +32.5 runs. For an individual player, WAR values may be calculated for single seasons or parts of seasons, for several seasons, or across the whole career of the player. Collective WAR values for multiple players may also be estimated, for example to determine the contribution a team receives from its outfielders, its relief pitchers or from specific positions such as catcher.〔http://www.fangraphs.com/blogs/mike-trout-top-ten-outfield/〕〔http://www.fangraphs.com/blogs/2013-positional-power-rankings-catcher/〕 It is also possible to extrapolate a future WAR value from a player's past performance data.〔http://www.fangraphs.com/library/principles/projections/〕 抄文引用元・出典: フリー百科事典『 ウィキペディア（Wikipedia）』 ■ウィキペディアで「Wins Above Replacement」の詳細全文を読む スポンサード リンク
|