Rajiv Maheswaran: The math behind basketball's wildest moves
拉吉夫· 马赫斯瓦兰: 篮球场上最疯狂步伐背后的数学原理
Using advanced data analysis tools, Rajiv Maheswaran and Second Spectrum help make basketball teams smarter. Full bio
Double-click the English transcript below to play the video.
by the science of moving dots.
背后的科学非常着迷。
in our offices, as we shop and travel
and around the world.
if we could understand all this movement?
不是一件很棒的事吗?
and insight in it.
我们生活在这么一个时代,
at capturing information about ourselves.
sensors or videos, or apps,
with incredibly fine detail.
where we have the best data about movement
最佳的数据来源之一
or football or the other football,
甚至运动员身上装上设备来追踪
and our players to track their movements
is turning our athletes into --
——你们大概已经猜到了——
and like most raw data,
难以处理,也没什么趣味。
and not that interesting.
basketball coaches want to know.
比如篮球教练想知道的事情。
because they'd have to watch every second
每一秒数据都记下来再去思考,
the game with the eye of a coach.
以教练的视角去看一场比赛。
我们让机器去观察些什么呢?
shots and rebounds.
slightly more complicated.
稍复杂点的事情,
and pick-and-rolls, and isolations.
Most casual players probably do.
没关系。打球的人大都了如指掌。
the machine understands complex events
with the eyes of a coach.
教练的视角去观察数据了。
something like a pick-and-roll,
估计会惨不忍睹。
it would be terrible.
in basketball between four players,
without the ball
guarding the guy with the ball,
嗒哒,这就是挡拆。
and ta-da, it's a pick-and-roll.
of a terrible algorithm.
he's called the screener --
或者叫掩护者——
but he doesn't stop close enough,
但停的位置不够接近,
and he does stop
it's probably not a pick-and-roll.
那也不算挡拆。
they could all be pick-and-rolls.
这些都是挡拆。
球员间距、位置而定,
the distances, the locations,
we can go beyond our own ability
我们就能超越自身的能力
Well, it's by example.
举个例子:
"Good morning, machine.
“早上好,机器。
and here are some things that are not.
features that enable it to separate.
区别两者的特征来。
to teach it the difference
“不妨用颜色和形状来区分吧?”
use color or shape?"
要区分事物的特征是什么?
what are those things?
the world of moving dots?
with relative and absolute location,
绝对位置、距离、时机、
of moving dots, or as we like to call it,
换成专业术语,
in academic vernacular.
you have to make it sound hard --
很难懂,很专业——
it's not that they want to know
才是他们关注的。
how it happened.
这儿我要解释一下。
So here's a little insight.
the most important play.
and knowing how to defend it,
and losing most games.
has a great many variations
是非常重要的,
is really the thing that matters,
机器的智能性要求相当高。
to be really, really good.
两个防守队员,
and two defensive players,
the pick-and-roll dance.
也可以放弃挡拆,
can either take, or he can reject.
或撤到一个无人盯防的空位。
can either go over or under.
或者从后方绕过掩护。
近距离防守,亦或者向后消极防守。
or play up to touch, or play soft
either switch or blitz
most of these things when I started
according to those arrows.
事情就好办多了。
但往往这些移动非常杂乱。
but it turns out movement is very messy.
要在查准率和查全率方面
these variations identified
a professional coach to believe in you.
才能让专业教练相信你的技术。
困难重重,
with the right spatiotemporal features
能够识别这些变化。
to identify these variations.
almost every single contender
相关的识别软件,几乎每个
on a machine that understands
其功能就是通过机器
that has changed strategies
我们还对如何改善战术提供建议,
very important games,
coaches who've been in the league
老教练愿意听取
advice from a machine.
it's much more than the pick-and-roll.
更让我们兴奋的是
with simple things
much of what it does,
to be smarter than me,
can a machine know more than a coach?
机器能否比教练懂得更多呢?
to take good shots.
it's a good shot.
通常来讲这球投不进。
by defenders, that's generally a bad shot.
“差”有多差,
or how bad "bad" was quantitatively.
using spatiotemporal features,
What's the angle to the basket?
投篮的角度是多少?
What are their distances?
他们间的距离,
我们能够通过观察球员的移动
at how the player's moving
and we can build a model that predicts
建立一个模型,
would go in under these circumstances?
这一单一行为得到
and turn it into two things:
and the quality of the shooter.
because what's TED without a bubble chart?
没有气泡图,还算什么TED呢?
and the color is the position.
颜色代表他们的位置。
we have the shot probability.
bad at the bottom.
47 percent of their shots,
takes shots that an average NBA player
is that there are lots of 47s out there.
球员中选择一个。
giving 100 million dollars to
how we look at players,
我们对球员的看法,
a couple of years ago, in the NBA finals.
there was 20 seconds left.
上去想投个三分追平。
came up and he took a three to tie.
named Ray Allen.
They won the championship.
最激动人心的时刻之一。
games in basketball.
the shot probability for every player
a rebound at every second
that we never could before.
I can't show you that video.
我无法给大家展示这个精彩片段。
about 3 weeks ago.
that led to the insights.
电脑追踪数据的演示。
This is Chinatown in Los Angeles,
在洛杉矶的唐人街,
the Ray Allen moment
that's associated with it.
of the professional players, it's us,
我们取代了专业球员,
announcer, it's me.
chance of happening in the NBA
会发生这样的时刻,
and a great many other things.
it took us to make that happen.
我们尝试了多少次才成功的。
并不是重点。
of every NBA game -- it's not that.
a professional team to track movement.
一个专业团队才能追踪移动。
player to get insights about movement.
去理解那些移动。
因为我们无时不刻不在移动。
sports because we're moving everywhere.
我们能学到什么?
pick-and-rolls,
the moment and let me know
迈出她的第一步。
any second now.
our buildings, better plan our cities.
更加好地规划我们的城市。
of the science of moving dots,
we will move forward.
更智能地移动,一路向前。
ABOUT THE SPEAKER
Rajiv Maheswaran - ResearcherUsing advanced data analysis tools, Rajiv Maheswaran and Second Spectrum help make basketball teams smarter.
Why you should listen
Sports fans can get obsessed with stats about player performance and game-day physics. But basketball, a fluid and fast-moving game, has been tough to understand through numbers. Rajiv Maheswaran is working to change that, by offering pro basketball teams insight into game data to make better decisions. Maheswaran is the CEO and co-founder of Second Spectrum, a startup transforming sports through technology. He is also a Research Assistant Professor at the University of Southern California's Computer Science Department and a Project Leader at the Information Sciences Institute at the USC Viterbi School of Engineering, where he co-directs the Computational Behavior Group.
His research spans various aspects of multi-agent systems and distributed artificial intelligence using decision-theoretic and game-theoretic frameworks and solutions. His current interests focus on data analytics, visualization and real-time interaction to understand behavior in spatiotemporal domains. Like, say, the spatiotemporal domain around a basketball hoop.
Rajiv Maheswaran | Speaker | TED.com