
Game theory article from a professional Starcraft player/caster. - thisisnotmyname
http://www.teamliquid.net/forum/viewmessage.php?topic_id=64514
======
bz
The concepts outlined are pretty good, but I want to make a counterpoint
against heuristics in general. Distilled ideas like these are certainly useful
for trying to grasp a complex system, but they do not, for the non-expert
player, represent game knowledge. Let me explain why.

The pitfall for the average viewer/player is to take these mantras and apply
them directly to what they see. They see a game where T apparently overcommits
after winning an engagement at his 3rd, and wonder why he didn't take a 4th
instead. Surely, this is a mistake of not getting more ahead!

An expert player might look at the same scenario and see an entirely different
picture. The problem was that he scanned a 15m timing instead of a 17m timing
for the Hive, so he was actually behind in that engagement (he should have
decisively won with the Z's gas locked up elsewhere!). And that Broodlords
would be due out in 2 production cycles, but it takes 3m for him to break-even
on the new mine, and he would miss the window to secure enough of an advantage
to push the game into a low-econ trade phase.

My point is that real game understanding is extremely specific. It's all about
the actual state and timing. To go back to the article, that's where the
marginal advantages are gained - by understanding and controlling how these
extremely specific scenarios play out. The larger ideas about strategy that
everyone loves fall out from the analyses of these interactions. But "getting"
the general idea isn't the same as actually _getting_ it when you work out
these scenarios and timings yourself from extensive playing/testing. So
heuristics are really only part of the picture, the much larger part is a
precise understanding of the system at work.

~~~
seri
That was awesome, sir. I love the attention to details in the scenario you
described and your analysis. I only picked up the hobby of watching Starcraft
about 6 months ago (I watch more Broodwar than Starcraft II), but I used to
play a lot, albeit at an amateur level. I watched popular casters like
diggity, Klazart, Nuke, and moletrap. However, sometimes I don't quite
understand why the winner wins even though I have consumed a lot of theories
in advance, perhaps for the exact reason you just pointed out. There are good
comments on Team Liquid every now and then but the site is hard to browse with
100 pages on average for a popular game.

Do you write game analysis like this somewhere, or do you know where I can
read something similar?

~~~
larrik
Day[9] (the author of the original essay), is easily the "go to" place for
this sort of thing. He has a great amount of analysis scattered throughout his
dailies, but here is a link to his most recent daily focusing on "how did I
lose" (assuming I remember this daily correctly).

<http://blip.tv/file/5460268>

Also,

<http://wiki.teamliquid.net/starcraft2/Day9_Daily>

has a good list of his videos, with their subject, etc.

------
patio11
My little brother, quoting a noted SC personality: when you're ahead, get more
ahead. It is probably the most important strategic lesson in the game: if you
have a temporary 5 pct material advantage, you can still easily get outplayed
if you force a fight. Better to turn that into a 10 pct material advantage,
etc, and force a fight only after you've already won.

The other game I play a lot of is League of Legends, and sadly the community
around my skill level has not learned this gospel yet. If it looks like we
have 30 seconds of advantage, the team of 5 almost invariably either does
nothing or goes for a decapitating stroke whose downside risk is loss. A
better tactic is probably "Get more ahead so we win the next skirmish, too,
snowballing until we win by concession or overwhelming force."

~~~
feral
"Sun Tzu said: The good fighters of old first put themselves beyond the
possibility of defeat, and then waited for an opportunity of defeating the
enemy. To secure ourselves against defeat lies in our own hands, but the
opportunity of defeating the enemy is provided by the enemy himself. [...]
Hence the skillful fighter puts himself into a position which makes defeat
impossible, and does not miss the moment for defeating the enemy."

* * * * *

I think the spirit of what is being said in 'The Art of War', is the same
principle that's being discussed in the article: Don't rush into striking
before you are sure of victory, and lose everything; instead use the advantage
to build yourself into an invincible position, with less risk.

* * * * *

'The Art of War' has been around a long time.

If there's a lesson here, its that strategy gamers might benefit from doing
some reading.

I liked the article, and thought it was good; but it comes across that the
author has no education in either (economic) game theory, or the study of game
playing AI (e.g. minimax, search based AI techniques like you'd see in a chess
AI etc). (Two related, but sometimes separate fields).

Which is fine - but there's a lot of good work in those fields, that strategy
gamers, that seek to understand games analytically, as well as intuitively,
would do well to read.

~~~
ido

        If there's a lesson here, its that strategy 
        gamers might benefit from doing some reading.
    

You have to play sc2 or similar games for years before that kind of advice
becomes applicable (since there is so much basic skill to pick up before the
game becomes that strategic), and by the time you know the game well enough to
find the correct analogy to something written in The Art of War you've
probably already discovered it yourself.

In short, I think there are very few if any sc2 players that would benefit (in
terms of improving their game at least) from reading The Art of War.

~~~
feral
>You have to play sc2 or similar games for years before that kind of advice
becomes applicable (since there is so much basic skill to pick up before the
game becomes that strategic), and by the time you know the game well enough to
find the correct analogy to something written in The Art of War you've
probably already discovered it yourself.

You seem to be saying that by the time they are playing at a level where
general strategic advice becomes applicable, they'll already have learned it.
This is a little circular.

Also, I think it probably takes a couple of months, before you get to the
strategic level, not years, but that's just an opinion.

~~~
ido

        You seem to be saying that by the time they are 
        playing at a level where general strategic advice 
        becomes applicable, they'll already have learned 
        it. This is a little circular.
    

Can you point where the circularity comes in?

I said that by the time the advice that can be learned from reading TAOW
becomes useful they would have already learned it from their "battle"
experience.

What I am saying is that reading it in book form will at most provide an "aha
- that's why this strategy I've been contemplating is good!" moment, rather
than a new idea about how to play the game.

I've been playing sc2 on and off (mostly off) since it was released and am a
diamond league player & most of the time the game is still more about paying
attention and tactics rather than high level strategy for me.

And I am pretty sure I would have not have even got to this level were I not
already a somewhat competent wc3 player.

Maybe if you play 10+ hours per week of sc2 _every week since it came out_ you
would not need years to master the game, but as a busy professional with
little free time and many games I doubt you could ever reach that level in a
matter of months without having played a lot of sc1/wc3 beforehand.

EDIT: take a look at
[http://wiki.teamliquid.net/starcraft2/Battle.net_Leagues#Lea...](http://wiki.teamliquid.net/starcraft2/Battle.net_Leagues#League_Mechanics)
\- 80% of players are at platinum league or less, where the game
_definitively_ requires more getting over basic tactics than high level
strategy. I would bet you can win with a marine/zergling/zealot rush in almost
every match in these leagues if you have sufficiently superior micro to your
opponent.

~~~
nickknw
> 80% of players are at platinum league or less

By definition, platinum or below is the bottom 80% of the player base. No
matter how good the sc2 population gets, around 80% will ALWAYS be platinum or
below.

That doesn't necessarily mean that the skill level for platinum or below will
always be static though. For example, the korean server is generally regarded
as more difficult. A platinum player on the NA server might only reach gold
there (or might still be platinum but lose more).

But you are definitely correct that their mechanics are the main thing that
separates most top players. I would emphasize macro as being much more
important than micro though.

------
herTTTz
As many of the sc2 players here might know, the guy who wrote this (day9) is
one of the famous person in esports right now. He used to be a professional
player of sc, but since sc2 appeared (2010) he dedicated to analyze the game,
and has even a daily show about it.

The interesting thing about starcraft is that it's played _so_ much (in s.
korea is a profession, kids actually go to live in "pro houses" were they play
all day), that the game has/is evolving to a point where every little thing
matters. In the highest levels, you can't really fight a straight up battle
and hope to win, it's a game of getting little advantages (like removing %1 of
his income) and trying to get ahead, and push those advantages much later on.
Increasing your economy, building up you army, the execution and management of
your units in the fight, everything counts.

~~~
endtime
The game is played at a high level, sure, but I'd call this a slight
exaggeration. 1% of a player's income is less than a single worker even in the
late game (when most players have around 70 workers), and a single worker kill
never really makes a huge difference.

~~~
jtchang
Depends when the kill is. A single worker from your initial 6? Big problem.

~~~
endtime
You can't even get a scout worker to your opponent's base before they're up to
9-10 workers or more on most maps. Anyway, killing one worker of 6 is 17% of
someone's economy, not 1%.

~~~
algorias
Killing a worker early is subject to compound interest, so that 17% (or 10%
more realistically) of an early worker kill is going to grow exponentially all
game long.

~~~
endtime
>an early worker kill is going to grow exponentially all game long.

That's a very unrealistic claim, though yes, losing a worker very early can
have a measurable effect. But that pretty much never happens, outside of all-
in cheeses like 6 pool or proxy 2 rax/gate.

Are you defending the original claim that games are decided over affecting 1%
of one's opponents economy?

~~~
jasonlotito
> the original claim that games are decided over affecting 1% of one's
> opponents economy?

The original claim wasn't that the game was decided over 1% of someones
economy. Rather, that games were decided over many small advantages gained,
things like affecting someones economy by 1%. You do that 5-10 times
throughout the game, and that's a good 5-10% of their economy.

~~~
endtime
Well that's not actually how games are decided these days. It's often
something like "did Z have queens blocking his ramp before the blue flame
hellions got there?" or "did P get scout the tech lab on the starport and put
down a robo in time?", even at the pro level. A lot of other games end with a
two-base timing attack (e.g. fast blink stalkers). Good games will have some
eco harass, but more along the lines of dropping 8 marines and killing several
workers, or totally taking out an expo with infested terrans. I don't think
I've ever seen a single worker kill be significant, or even multiple instances
of similarly small magnitude. The APM and attention it costs to harass often
isn't worth killing a single worker.

There's a lot of depth to SC2, but I think it's a mischaracterization to say
that it's a game of such tiny advantages, at least at the level it's played
today.

------
jarin
Sean "Day[9]" Plott (the author of the article) is probably the best
analytical Starcraft II caster around. His "Day[9] Dailies" cover everything
from the absolute fundamentals ("here's how you set up your hotkeys, here's
how you keep your money low") to more advanced topics like build orders,
expanding, tactics, and micro. He also throws in "Funday Mondays", where
beginner and experienced players alike try to win with unorthodox constraints
(usually with funny and/or insightful results).

Bronze league matches often end up being a contest of who can win with the
first rush or the earliest "cheese", but most pro-level play does end up being
a careful balance between aggression, defense, and expansion. The winner is
usually the one who can stay just slightly ahead of their opponent until they
can seize a clear advantage.

~~~
makmanalp
Slightly unrelated but Day9 also had a really good daily on what it is to
dedicate yourself to something for a very long time. Great bits and pieces for
any entrepreneur and worth watching if you even know anything about starcraft:

<http://www.youtube.com/watch?v=NJztfsXKcPQ>

Edit: 0:28:45 - On strategy and execution

~~~
Periodic
I really enjoyed watching that, though not really from the standpoint of an
entrepreneur. What I really took from that video was how important a support
structure is. It sounds like he wouldn't have gone as far as he did without
his brother and mother being behind him 100% for years. Every time he had a
failure, there were people there to help him get past it and learn from it
instead of getting discouraged. He gained this support structure by being so
passionate about his game that he _made_ his mother believe in him.

~~~
makmanalp
> Every time he had a failure, there were people there to help him get past it
> and learn from it instead of getting discouraged.

> being so passionate about <x> that he made <y> believe in him

IMHO, this sounds like two pieces of sage advice for entrepreneurs already :)

------
lobo_tuerto
There is no _Game theory_ mentioned anywhere in the article, but _Competitive
game design theory_.

Title should be changed to reflect that as to not bring confusion about it
referring to the broad (and complex) Game theory subject.

------
seri
Day9 hosted an event called The After Hours Gaming League in which eight tech
companies will compete each other for charity. The event has just finished its
first season with team Microsoft crushing everyone else. Zynga is the runner
up and Google claimed third place.

Games: <http://www.youtube.com/results?search_query=ahgl> Homepage:
<http://afterhoursgaming.tv/>

There are a number of interesting game theory articles on competitive
Starcraft. This is one:
[http://www.teamliquid.net/forum/viewmessage.php?topic_id=258...](http://www.teamliquid.net/forum/viewmessage.php?topic_id=258566&currentpage=125#2488)
(and my comment to it:
[https://plus.google.com/116918963723558831013/posts/A8DRTY11...](https://plus.google.com/116918963723558831013/posts/A8DRTY11MYQ)).

~~~
ralfd
I was really impressed how Microsoft steamrolled everyone!

~~~
seri
I was less impressed with Microsoft's performance than their team spirit.
After all, the mere fact that MSFT has way more employees than the other teams
already means that they should be stronger. However, I was surprised that they
set up an internal league to select who will get to play, and that there were
many MSFT people watching together live on the grand finals day. It just seems
like they _take fun seriously_ (to quote Day9 himself), and that's pretty cool
IMO.

------
monkeypizza
The new 4-5dan go-playing bots on kgs (zen19d, crazystone) use this strategy
extensively. When they're ahead they play to consolidate their biggest
weakness, and when they're behind they play more and more risky moves to try
to come back. In the endgame the calculate the score exactly, and will play
negative point value moves as long as they are ahead on the board.

It makes for a really tough game, cause if you do get ahead, you have to face
a series of attacks which _almost_ but don't quite work, and if you mess up
any of them it's over.

~~~
aidos
My Go teacher once told me that the truely great players will hold a game in
near perfect balance throughout. Concerningy, are the computers really at 4
dan now? I ain't never going to beat the machines.

~~~
monkeypizza
yeah, they have really gotten good in the last year. They've gone from better
than 90% of players who have ever played go, to better than 95%+. They are
great to watch, too, merciless and play interesting moves.

Check out crazystone's stats:
[http://kgs.gosquares.net/index.rhtml.en?id=CrazyStone&y=...](http://kgs.gosquares.net/index.rhtml.en?id=CrazyStone&y=2011&m=7&r=0)

72% win percentage as a 4d.

------
jaredmck
This marginal advantage strategy is also well demonstrated in professional
tennis. When you are in control of the rally, going for a shot which maintains
your offensive position, with the potential to slightly extend your lead
within the rally, is best. Often the defensive player will go for a huge
winner if they are getting tired or are so out of position as to be unable to
recover by hitting several good marginal defensive shots to get the point back
to a neutral position. But if you watch the best players, they all have skills
which gain or erase the most marginal advantages.

~~~
ralfd
Tennis, yes! And I would guess also Basketball and other games with small but
many incremental scoring.

I read some time an article in which was argued, that this is a fundamental
difference in Soccer compared to other team sports. As there is often only 1-2
goals in Soccer a Toss-up between a top team and an underdog is more likely.
It is even often the case that a team is playing dominating but they lose
anyhow, because the weaker team is getting lucky and stumples the ball in the
goal. This keeps the sport fresh and interesting and is seen by fans as a
virtue. The randomness is then cancelled out over the season and marginal
advantage is important in competition for the league championship.

------
marcamillion
Am I the only one that thought this post would have been about Economic Game
Theory? - <http://www.dklevine.com/general/whatis.htm>

Very nice read though. Day9 is right. The best players all seem to have a
knack for maintaining a marginal advantage or taking a small one and getting a
bigger advantage.

------
edsrzf
If I remember correctly from my college AI days, thinking about upcoming turns
and minimizing your opponent's gains is called minimax:
<http://en.wikipedia.org/wiki/Minimax>

I'm surprised that there was only one AI in the competition that did this. We
were all expected to use this strategy in my class. Once everybody's figured
this out, it becomes a game of:

\- Who can think ahead the most turns? \- Who has the best "am I winning?"
heuristic function? (For Mancala this function is fairly obvious, but for many
games it's not.)

~~~
gcp
I agree, the Mancala backstory sounds quite strange and unbelievable. To me it
looks like it's made up (maybe partly on some vague recollection of the
author) to serve as an introduction for the rest of the article.

The behavior of AI programming winning by 1 point does exist in real life for
Monte-Carlo based agents calculating winning probabilities. You can see it in
computer go games.

~~~
andfarm
It's almost certainly based on the author's experience in Harvey Mudd's CS 151
(Artificial Intelligence) course, in which developing a Mancala AI is a
standard project.

~~~
sireat
I believe Day 9 did indeed get his masters this year from Harvey Mudd.
(original article was written 4 years ago)

~~~
eavc
Masters this year from USC, undergrad at Hervey Mudd.

------
roel_v
Note that this article isn't on _game theory_ , but on _game design theory_
(i.e., 'game' as in 'computer game').

------
frankiewarren
The author stated, "Third, a good competitive game should test a player’s
skills and minimize the element of chance or luck. Ideally, the probability of
a weak player defeating a good player should be as close to zero as possible."

Do you think this is always the case? I'm thinking about texas hold 'em, which
has short-term variability but the stronger players win over the long run with
a better strategy. Does chance have a place in competitive gaming?

~~~
lionhearted
The relevant quote here is, "People don't gamble on Chess."

A luck element lets players of uneven skill feel engaged. Even better is a
great handicapping system like Go has, but that's notoriously hard to design.

Chess is a great game at certain skill levels and has a lot of beauty to it,
but games with enough of a skill difference aren't really interesting for
either player unless the better player is teaching/mentoring.

So yeah, luck has some place in letting different people (and even gamble)
together.

~~~
erikb
I know some people who actually gamble on chess. The thing is, that even with
a perfect game (not saying that chess is perfect) you still have the human
factors involved. The spirit, the concentration of both players today, the
pressure involved when betting money or playing in front of observers. There
is still a lot of margin left.

------
kylek
For those that aren't familiar with it, the teamliquid.net forum typically has
very high-quality posts (i.e. heavily moderated) and a great resource for
anyone interested in e-sports. I recommend you check out the front page if you
haven't before.

------
Triumvark
This article correctly notes that those in the lead should play to
conservatively extend their marginal advantage.

The corollary, for those in behind, is that they should attempt more gambits.

The principles of variance are strange. Sometimes, if you're in behind, you
reduce your chance of losing by adopting what looks like a "losing" strategy
(according to naive expected value calculations). With a wild all-or-nothing
strategy, your chance of winning from behind likely won't exceed 50%, but by
acting more like the 'risky amateur,' you might up your chances from 10% to
30%.

------
d0m
In my opinion, the most important concept to understand is "Timing windows".
Vs a equally skilled player, you can't have all the advantages. Understanding
the _imbalances_ of a current situation - and taking advantage of it - is
really what differentiate beginners from great players.

Sometime, in a game of 30mins, there's only a few seconds where you have the
upper hand.. and this is where you need to attack. Miss that moment (from a
couple of seconds!!) and you lose. Go a little bit before, and you lose!

------
d0m
So much stuff can be learned from sc/sc2 to apply in your life. Things from
accepting defeat and understanding your mistakes, to know how to fight
strategically. (By _fight_ I mean it in a very vague way; Fight for a girl,
Fight for a new job, etc.)

------
wtvanhest
I just read all the comments because the author states that one program
collects the maximum amount of stones, and another competitor's program
figured out how to collect an additional stone.

Does this not make sense to anyone else? Can someone please explain it to me?

~~~
colanderman
My understanding was that the competitor's program collected a strategic
number of stones N in such a way which forced the other program to be able to
collect at most N-1 stones on its next turn. I'm not familiar with the rules
of Mancala but I presume they allow for strategies such as this.

------
popisdead
this is a life lesson, not a game design theory lesson!

------
d0m
I browse hacker news and reddit/r/starcraft each day.. I love when an article
appears on both :) A perfect mix between _hacker_ -ness and _gamer-_ ness.

------
CosmicShadow
great article, good reminders of how to build a great competitive game, which
is applicable to me!

------
leon_
So much time and resources wasted on a game. My heart bleeds.

------
metatronscube
Not Game Theory really, but Ender Wiggin has some good points...pitty its just
a game.

