作者d88647511 (Ricky Rubio)
看板LeBronJames
標題[轉錄][外電] Using Math To Determine the Ballhogs
時間Sun Mar 20 23:13:42 2011
※ [本文轉錄自 Thunder 看板 #1DXUq8jl ]
作者: poning (今天總算有太陽) 看板: Thunder
標題: [外電] Using Math To Determine the Ballhogs
時間: Sun Mar 20 20:03:17 2011
數學或統計我都不會…內容自然以英文為準，
翻譯有錯的話請指正！
===
http://tinyurl.com/46t5ec6
Using Math To Determine the Ballhogs
Even the casual fan knows the NBA is full of chuckers—those frustrating
players who hoist up fade-away jumpers in the face of a double-team. But with
the help of advanced math, we can finally pinpoint the greatest offenders.
即使是普通的運動迷都知道NBA有很多濫投王---這些令人沮喪的球員，面對包夾，依舊會
來個後仰跳投。但是透過進階數學的幫忙，我們終於可以找出誰是最濫投的球員了。
Matt Goldman, a graduate student at the University of California, San Diego,
and Justin Rao, a research scientist at Yahoo Labs, have identified the three
biggest "overshooters" in the NBA: the Thunder's Russell Westbrook, the
Bobcats' Tyrus Thomas and the Lakers' Lamar Odom. Conversely, they named the
Hornets' Chris Paul the biggest "undershooter."
Matt Goldman是一名加州大學聖地牙哥分校的研究生， Justin Rao則是Yahoo Labs的研究
員，他們兩位已經列出三名NBA最嚴重的濫投王是誰了---Russell Westbrook、Tyrus
Thomas與Lamar Odom。同時他們也認為Chris Paul是NBA最該多投一點的謙虛型球員。
To compile the lists, the researchers tracked 400,000 possessions over the past
four full seasons and noted the time on the shot clock when the first shot went
up (they excluded fast-breaks). Then they used a statistical procedure known as
a "Maximum Likelihood Estimation" to find each player's "marginal shot"—the
most difficult shot each player is consistently willing to take. Using this
information, the researchers were able to analyze when in the shot clock each
player takes these low-percentage shots and how efficient he is at making them.
Finally, they ran a statistical test to see how a player's shot selection
compares to how his team would have fared otherwise. The results showed which
players would help their team by taking more difficult shots and which should
be more bashful.
為了完成這個名單，他們追蹤了過去4個球季約400,000次的進攻次數，並紀錄24秒進攻時間
內，第一次出手的時間（他們扣除快攻）。他們使用最大近似值(Maximum Likelihood
Estimation)這個統計方法來找出每個球員的「貧乏的投籃」---意指在他們所有投籃之中最
困難的、對手球員樂於看見的投籃。利用這些資訊，研究者得以分析每個球員在進攻時間內
命中率最低的投籃是發生在何時與每個投籃的效率值為何。最後，他們進行顯著性檢驗
(statistical test)來觀察球員的投籃選擇與球隊得到利益或否。統計結果表示出哪個球員
最應該多嘗試投籃，哪個球員應該要謹慎一點。
Goldman said overshooters are generally players who try to create shots too
early in the shot clock. In Westbrook's case, the Thunder would be better off
if he passed more. Undershooters, meanwhile, are often stars who choose not to
shoot as much as they probably should—LeBron James should have actually shot
more during his time with Cleveland.
Goldman說濫投王一般來說是那種進攻時間剩很多的時候就投籃的人。對雷霆的Westbrooks
來說，如果他多傳球，會對球隊比較好。相反的，謙虛型的球員，就算是該他投的球，很多
時候也會選擇不要投。話說LBJ在騎士時確實應該多投一點。
—Jared Diamond
===============================================================================
Who Shoots Too Much?
誰投太多球？
Over the past four full seasons, here are the NBA's biggest "overshooters" and
"undershooters," based on a formula that estimates when a player should shoot
and when he'd be better off passing.
以下是根據過去四個完整球季的資料，以上面提到的統計方法，統計出來的該多傳球
的濫投王與該自私點的謙虛型球員。
OVERSHOOTERS (Rating*) UNDERSHOOTERS (Rating)
濫投王 太謙虛啦！
Russell Westbrook (-2.98) Chris Paul (+5.34)
Tyrus Thomas (-1.98) Brandon Roy (+5.13)
Lamar Odom (-1.94) LeBron James (+4.93)
Monta Ellis (-1.91) Al Jefferson (+4.62)
*Zero is an optimal rating
*0是理想中最佳值
--
哲學的義務，是去除因誤解而生的幻想。
--
※ 發信站: 批踢踢實業坊(ptt.cc)
◆ From: 220.132.168.231
※ poning:轉錄至看板 NBA 03/20 20:03
推 ololool:ML Estimation就是去算最大事後機率的估測 03/20 20:13
→ ololool:Statistical test應該是假設檢定之類的方法 03/20 20:14
→ ololool:在統計裡可以幫資料分門別類 03/20 20:14
→ ololool:不過反正都不是重點XD 用統計方法算出來小寶果然是濫投哥 03/20 20:15
→ poning:他前兩年確實很悲劇阿～今年也只是因為變準了所以才比較好 03/20 20:21
推 arkod:好一個事後機率 ... 現在要幫大家上偵測與評估的課嗎 XD 03/20 20:55
推 garypayton5:正面思考...果斷!勇於出手!! 03/20 20:57
→ d88647511:原PO可以借轉嗎? 感恩 03/20 23:08
→ poning:可以阿 不過要轉哪個板阿～ 03/20 23:09
→ d88647511:LBJ版 裡面有提到QQ 03/20 23:11
→ poning:喔喔～了解 不嫌棄的話 請轉吧 03/20 23:12
--
※ 發信站: 批踢踢實業坊(ptt.cc)
◆ From: 140.122.32.81
→ d88647511:其實我也覺得LBJ要釋出控球權但是要多出手 03/20 23:14
→ d88647511:就樣喬丹一樣 三角裡面的喬丹持球變少但是得分一樣猛烈 03/20 23:16
推 w61036:其實看不太懂 好像沒看到很了不起的分析XD 03/20 23:20
→ w61036:不過 是沒注意他之前的出手數是多少 不過想說應該至少都20 03/20 23:21
→ w61036:次以上 本以為爛投他榜上會有名XD 後來想想他進攻效率真的 03/20 23:21
→ w61036:高XDD 03/20 23:21
→ d88647511:濫投表示不該出手還出手 LBJ這種得比較少 03/20 23:26
→ d88647511:我覺得這數據沒有經過考驗 不過也算是可以參考一夏XD 03/20 23:26