※ [本文轉錄自 NY-Yankees 看板]
作者: leddy (耿秋) 看板: NY-Yankees
標題: [統計]Zone Rating的進一步說明
時間: Wed May 16 16:46:01 2007
針對先前版友echomica提的防守區域內外的定義, 找了一下發現這篇
Chris Dial對Zone Rating的進一步解釋, 順便翻譯一下:
soure from http://0rz.tw/a42FA
Saturday, November 05, 2005
What is Zone Rating?
What is Zone Rating?
什麼是防守區域評價
Basically, ZR is the percentage of balls fielded by a player in his typical
defensive ‘zone’, as measured by STATS reporters.
基本上，防守區域評價(ZR)是防守球員在屬於他(典型的)的防守區對於球守備的百
分率，由STATS的記錄員進行測量。
The first part of understanding Zone Rating is understanding how the field is
divided up.
瞭解防守區域評價的第一步是要先知道球場在作防守區域評價時是如何畫分的。
The field is divided into 22 equal ‘slices’. Each slice runs from home
plate to the outfield fence. The first slice running along the left field
line is Zone ‘C’. (Zones A, B, Y and Z are in foul territory). The last
zone is Zone ‘X’. Like any ‘pie’ slice, or wedge, gets wider as you
approach the outfield wall. Zone C is about 7 feet wide at the third base
bag, and about 20 feet wide at 300 feet from home plate.
The next 21 zones (D - X) divide the field equally until you get to the right
field line. The dividing line between zones M and N runs right over second
base, splitting the field in half.
球場被切割成22個相等的"片狀"，每一片是從本壘板延伸到外野的牆。第一個片狀
是延著球場左側界外線, 即是區域"C" (A, B, Y和Z區域則是在界外區)。最後一個區域
則是區域"X"。就像任何"派"的片狀, 或楔子型，越接近外野的牆範圍變得越大。區域C
在三壘壘包大約是7呎寬，在距離本壘板三百呎時大約是20呎寬。
往下21個區域(由D到X)則是到球場右側界外線將球場分為相同的21個片狀。區域M和
N的分割線正好穿越二壘的壘包，將球場分成兩半。(詳情請看以下網址的圖)
STATS ZR zone grid
STATS ZR 防守區域的格子如以下網址所示
http://www.baseballthinkfactory.org/szymborski/zrgrid.jpg
(註：橫向分為22塊，縱向則用距離分為8分，這是STATS的分法，共176格
John Dewan則分為260, 目前找不到圖，我猜應該是26 x 10的分法)
With this division of the field understood, ZR becomes much easier to
visualize.
有了對球場區域劃分的瞭解後，防守區域評價(ZR)就變得更容易去想像。
For infielders, only ground balls are considered for zone rating. Line
drives, pop-ups and fly balls are not included. This serves to, oh so
slightly, under-rate the defensive value of all infielders, but presently
this information is not readily available. First basemen are responsible for
all bunts that travel more than 40 feet and land in his area of
responsibility.
對內野手而言，防守區域的評價只考慮到滾地球。平飛球，小飛球(不營養飛球)和
高飛球則並未納入。這種作法，可能稍許低估了所有內野手防守的價值，但目前滾地球
以外的資訊還不容易取得。一壘手負責所有超過40呎同時落在他防守區域內的犧牲觸擊
球。
Zones of Responsibility
防守責任的區域
While each ball is recorded for location, distance and speed, not every ball
is a defensive player’s responsibility. That is, only balls that could
reasonably be fielded from a typical defensive position are considered to be
in a player’s zone.
雖然每一球都記錄了位置，距離和速度，但不是每一球都是防守球員所需負責的。
換言之，只有球是落在典型的防守的位置，合理地能被守備球員接捕，才被落入防守球
員的防守區域。
Infield
內野
First Base: The first baseman is responsible for covering zones V through X,
the three zones closest to the right field line. This includes all grounders
hit within approximately 25 feet of the right field line, and anything right
up the line as well.
一壘：一壘手的防守責任涵蓋了區域V到區域X，這三個區域是最接近球場右邊的界外線。
防守責任包括了所有打向接近右邊界外線25呎範圍內，以及任何恰好落在右邊界外線上
的滾地球。
Second Base: The second baseman is responsible for zones O through T. The
left boundary of Zone N is second base, so the right boundary (about 8 feet
from second) is where the second baseman’s zone starts, and runs up to Zone
U. Notice that Zone U is not in anyone’s zone. It is ‘the hole’ on the
right side and not an infielder’s ‘responsibility’.
二壘：二壘手則負責從區域O到區域T。區域N的左線是二壘，所以區域N的右界(大約從二
壘壘包八呎左右)是二壘手防守區域的開始處，然後延伸至區域U的左界。注意區域U不屬
於任何野手的防守區域，這裡是球場內野防守"漏洞"的所在並不屬於任一個內野手的責
任區。
Third: The third baseman is responsible for covering zones C through F, the
four zones closest to the left field line. This includes all grounders hit
within approximately 35 feet of the right field line, and anything right up
the line as well.
三壘：三壘手的防守責任區涵蓋了區域C到區域F，這四個區域是最接近球場右邊的界外
線。防守責任包括打到到接右邊界外線35呎的範圍內，以及任何恰好落在界外線上的滾
地球。
Shortstop: The shortstop is responsible for zones H through L. The right
boundary of Zone M is second base, so the left boundary (about 8 feet from
second) is where the shortstop’s zone starts, and runs up to Zone G. Notice
that Zone G is not in anyone’s zone. It is ‘the hole’ on the left side and
not an infielder’s ‘responsibility’.
游擊手：游擊手則負責從區域H到區域L。區域M的右界是二壘。所以區域M的左界(大約從
二壘壘包8呎左右)是游擊手防守區域的開始處，然後延伸到區域G的右界。注意區域G也不
屬於任何防守員的防守區，這區域就球場內野防守"漏洞"的地方，不屬於任何內野手的防
守"責任區"。
Outfield
Outfielders are assigned two zones: one for line drives and one for fly
balls. Since line drives aren’t in the air as long, they have smaller zones.
外野：
外野手被分派兩大責任區塊：一個區塊是平飛球，另一區塊則是高飛球。因為平飛
球在空中飛行的時間不長，因此此區塊較高飛球為小。
For a ball to be assigned to an outfielder, it must travel a certain
distance. Corner outfielders are responsible for all line drives in their
zones that travel between 280 and 340 feet. They are also responsible for all
fly balls and popups that travel over 200 feet. The center fielder is
responsible for all line drives between 300 and 370 feet and all fly balls
and popups over 200 feet.
當打出的一球被指定為一個外野手的責任時，此球必須飛行某段的距離。左右外野手
負責飛越到他們防守區域，距離在280至340呎平飛球。他們也負責所有的高飛球，以及
飛行超過200呎的小飛球(不營養飛球)。中外野手負責所有飛行距離在300吋到370呎的平
飛球，以及所有的高飛球及超過200呎的小飛球。
The left fielder is responsible for Zones F through H on line drives and C
through I on fly balls and popups. Zone J between the centerfielder and left
fielder is unassigned.
左外野手負責區域F到區域H的平飛球，以及區域C到區域I的高飛球和小飛球。區域
J界於中外野手和左外野手之間，未指定為任何野手的責任區。
The center fielder is responsible for Zones L through O on line drives and K
through P on fly balls and popups.
中外野手負責從區域L到區域O的平飛球，以及區域K到區域P的高飛球及小飛球。
The right fielder is responsible for Zones S through U on line drives and
Zones R through X on fly balls and popups. Zone Q between the centerfielder
and right fielder is unassigned.
右外野手負責從區域S到區域U的平飛球，以及區域R到區域X的高飛球和小飛球。區
域Q界於中外野手和右外野手之間，同樣未指定為任何野手的責任區。
On line drives, the zones J and Q are unassigned between the outfielders,
while on fly balls, those zones are covered.
對平飛球而言，除了區域J和區域Q外還有一些未指定給外野手的區域，但是對高飛
球而言這些區域則涵蓋在野手的防守區域內。
Using these zones, STATS determines how many balls are hit into each fielder’
s area of responsibility. An infielder’s zone rating is equal to the number
of outs made divided by the number of balls hit into the player’s zone. ‘
Outs Made’ equals every ball fielded within the zone that is turned into an
out, plus all balls fielded outside the zone turned into an out. When a
player fields a ball outside his zone and turns it into an out, it is counted
as both an out and a ‘ball in zone’ for the purposes of calculating his
zone rating. This is a flaw in ZR, as balls outside the zone should be
counted only as an out. Otherwise it takes away a “range” aspect of the
rating.
運用這些區域的劃分，STATS決定有多少球被打進每個野手防守責任的區域。一個內
野手的防守區域評價是等於野手拿到的出局數除以打進野手防守區域內的球數。拿到的出
局數等於在防守區域內防守到的球轉換為一個出局數，加上打出防守區域外完成的守備達
成的出局數。當一個防守球員在防守區域外完成守備，此守備同時被計為一個出局數及一
個"防守區域內的球"("ball in zone")，以便計算他的防守區域評價。這是舊的防守區域
評價(ZR)的缺失處，防守區域外完成的守備應該只計為一個出局數較好。或是另外將此數
字作為"防守範圍"層面的評價。
(STATS ZR的缺失在先前Sean Smith的文章中已經提過，這也是為何Dewan要提出新的ZR算
法的原因，產生了另外計算防守區域外出局數(ZOO)的算法)
An outfielder’s zone rating is equal to balls hit into his zone which do not
result in hits, divided by the number of balls hit into his zone. The player
is credited with both an ‘out’ and a ‘ball in zone’ for balls caught
outside his zone, just like the infielders.
一個外野手的防守區域評價等於打進其區域內未變成安打的球數，除以打進其防守區
域的球數。一個防守員在防守區域外完成的守備，同樣同時計為一個"出局數"和一個"防
守區域內的球"，算法跟內野手計算的方法相同。
This explains exactly how the zones are defined. The reason these zones were
selected is because these are the zones where balls are turned into outs at a
greater than 50% rate. The greater zone is not so much arbitrary, as drawn
from a reasonable expectation that a fielder should make the play, since his
peers do.
上述的內容精確地說明了防守區域如何定義。這些區域的選擇是因為以這些區域計算
出局數，出局的比例是大於50%。大一點區域的決定不是那麼武斷的，而是從隊友眼中一
個野手應該能夠完成守備(拿到出局數)的合理預期所作的決定。
Chris Dial Posted: November 05, 2005 at 12:01 AM
後記：
另外Dewan的算法和STATS還有一個差異是，DP在STATS算為兩個出局數，但Dewan認為應該
純以區域內完成的出局數計算，所以只計1次，因為雙殺的另外一個出局數，應該是傳球後
才達成的，故只計一次比較正確。
越看越覺得學問頗大，若有興趣看看Chris Dial的部落，連問題都頗有學問。