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How David Beats Goliath

18 Post author: JulianMorrison 05 May 2009 01:25AM

From the New Yorker:

It was as if there were a kind of conspiracy in the basketball world about the way the game ought to be played, and Ranadivé thought that that conspiracy had the effect of widening the gap between good teams and weak teams. Good teams, after all, had players who were tall and could dribble and shoot well; they could crisply execute their carefully prepared plays in their opponent’s end. Why, then, did weak teams play in a way that made it easy for good teams to do the very things that made them so good?

[...]

David’s victory over Goliath, in the Biblical account, is held to be an anomaly. It was not. Davids win all the time. The political scientist Ivan Arreguín-Toft recently looked at every war fought in the past two hundred years between strong and weak combatants. The Goliaths, he found, won in 71.5 per cent of the cases. That is a remarkable fact. Arreguín-Toft was analyzing conflicts in which one side was at least ten times as powerful—in terms of armed might and population—as its opponent, and even in those lopsided contests the underdog won almost a third of the time.

[...] What happened, Arreguín-Toft wondered, when the underdogs likewise acknowledged their weakness and chose an unconventional strategy? He went back and re-analyzed his data. In those cases, David’s winning percentage went from 28.5 to 63.6.

[...]

Arreguín-Toft found the same puzzling pattern. When an underdog fought like David, he usually won. But most of the time underdogs didn’t fight like David. Of the two hundred and two lopsided conflicts in Arreguín-Toft’s database, the underdog chose to go toe to toe with Goliath the conventional way a hundred and fifty-two times—and lost a hundred and nineteen times.

Comments (25)

Comment author: Yvain 05 May 2009 11:27:45PM *  12 points [-]

Color me skeptical. Consider that if David's winning percentage is 63.6, being weaker is actually an advantage, and Goliath's optimal strategy is to abandon most of your resources in order to become the new weakling. That doesn't make a lot of sense.

I'd really like to see Toft's criteria for including wars, for deciding the winner, and for deciding whether David was using the optimal strategy. The only unbiased way to do this would be to have the categorization done by a third party who had no idea what the object of the experiment was. For best results, by several people working independently. And did he include all the hundreds of little wars between the US and various Native American tribes?

Or did he just take some famous wars (probably famous precisely because they were very close or had surprising results), call the ones where the smaller side did really well "David using an unconventional strategy", and then proclaim an unusual number of victories?

Even if the experiment was done correctly, asymmetric conflicts in wars can't really be generalized. Often it's something like "Big country tries to colonize little country", in which case little country is fighting on its own ground and just needs to make big country annoyed enough to go away. There's a big difference between that and basketball.

Speaking of basketball, in a lot of games there are successful but unstable strategies. Imagine a game where there are strategies 1-99, where each strategy is more likely to win, but also takes an increasing level of expertise. Imagine also that Strategy 5 has a special property - it beats any strategy numbered in the 90s, but no other. Imagine also that it takes some training investment to use a strategy - you can't just switch strategy numbers willy-nilly.

Matches between masters of this game will tend to look like 98 vs. 95 or something. A beginner may step in, use Strategy 5, and win a few games against masters who were expecting him to also be a master. But eventually the masters will switch to Strategy 89, and massacre the beginner. After all annoying beginners have been eliminated, the masters will go back to fighting among themselves at the 90s level. I can't think of a good example now, but I remember exactly this sort of thing happening in a few sports.

I wonder if the full-court press might be equivalent to strategy 5 here - something that other basketball teams could defeat, if they put in a bit of extra training, but since everyone knows that no one uses it no one trains to defeat it.

One last thing: I think my post Help, Help, I'm Being Oppressed is relevant here. The article plays a kind of dirty trick to get our sympathy on David's side: it says that the Goliaths are trying to alter the rules to form a cartel to prevent David's brilliant but unconventional strategies from allowing him to compete on a level playing field. Because that's how overprotective that evil Goliath is of his advantages and power.

But imagine the situation was reversed. David, through sheer pluck and spunk, was managing to win in the traditional way, and Goliath used a dirty trick generally considered to be against the rules, like using his vast monetary resources to hire a computer scientist to design an unbeatable fleet by AI. We would immediately scream "foul!" and be outraged that David's shot at the prize was being taken away so unfairly.

So we need to make sure we're uncoupling the question of whether we're rooting for David or Goliath, from the question of whether it's okay to win using dirty tricks that violate the spirit of a game and potentially make it less fun for everyone else.

Comment author: JGWeissman 06 May 2009 12:12:18AM 1 point [-]

Consider that if David's winning percentage is 63.6, being weaker is actually an advantage, and Goliath's optimal strategy is to abandon most of your resources in order to become the new weakling.

David's winning percentage is reported as 63.6 when he actually assesses his strengths and weaknesses, and adopts a strategy that plays to his strength and hides his weakness. Goliath's optimal (meta) strategy would be to do the same thing, to use a strategy that uses his strength and avoids his weakness.

On the other hand, the data may indeed be tainted by a defender's advantage as you suggest. If Goliath discovers that his strength is that his army has a lot of soldiers, and his weakness is that supporting so many soldiers in an occupied territory involves vulnerable supply lines, his best strategy might be to not invade other countries.

Imagine a game where there are strategies 1-99, where each strategy is more likely to win, but also takes an increasing level of expertise. Imagine also that Strategy 5 has a special property - it beats any strategy numbered in the 90s, but no other.

I would expect the best competitors in this game to prepare to use strategies 5, 89, and the best strategy in the 90's they can handle, and use a meta strategy of switching between these in response to their opponent's strategy. Such a team would defeat another that focused on a higher 90's strategy at the expense of strategy 89, would not be vulnerable to beginners who only know strategy 5, and would still be competitive when the masters switch to strategy 89.

Comment author: RobinHanson 05 May 2009 05:46:31AM 12 points [-]

I worry about selection effects - maybe underdogs only choose unconventional strategies when they could think of one that seemed promising.

Comment author: Eliezer_Yudkowsky 05 May 2009 08:37:33AM 11 points [-]

Maybe underdogs usually back down from overdogs entirely unless (a) they think of a way to win (b) they're stupid.

Comment author: jimrandomh 05 May 2009 05:52:34AM 6 points [-]

More importantly: maybe the fact that an underdog existed at all is only likely to be recorded if they won.

Comment author: JulianMorrison 05 May 2009 08:39:38AM *  -1 points [-]

When have victors ever been shy to boast? But what might be lost is the detail of the underdog's strategy.

Comment author: jimrandomh 07 May 2009 03:24:35AM 3 points [-]

Consider the case of rebels trying to secede from a larger nation. If they fail, then history will record that a rebellion took place. If they succeed, then history will record that a civil war took place. The study only looked at "wars".

Comment author: JulianMorrison 05 May 2009 06:44:51AM -1 points [-]

Even so, why didn't they look harder? It's the generalized willingness to quit and take a loss that's surprising.

Comment author: Psy-Kosh 05 May 2009 04:54:30AM 4 points [-]

Interesting. What happens though when goliaths use david strategies?

Comment author: AnnaSalamon 05 May 2009 03:03:42AM 4 points [-]

Thank you for this link, JulianMorrison. The article makes me more hopeful, and opens up my mental search space, re: existential risk.

Comment author: JulianMorrison 05 May 2009 01:33:54AM 5 points [-]

One interesting pattern in there, that the article doesn't draw into a conclusion - the two main examples presented, Eurisko and the basketball team, both were faced down by unofficial officials who tried to get them to conform and lose - and they backed down.

I would have gone for the kill. Let them cancel the tournament, let the ref foul the game. Ultimately, being too conciliatory cost them the war.

Taking the broader view, I wonder how much complaining about cheats is really an attempt by Goliath to have slings declared unfair. And how much of the desire to be nice and conform is evolution telling David to fall in line.

Comment author: Matt_Simpson 05 May 2009 02:13:36AM 4 points [-]

Taking the broader view, I wonder how much complaining about cheats is really an attempt by Goliath to have slings declared unfair. And how much of the desire to be nice and conform is evolution telling David to fall in line.

When debating the rules of a game, the "unfairness" defense always seemed daft to me. The rules are almost assuredly fair in that they don't favor anyone explicitly and are almost assuredly unfair in that they favor someone implicitly. It's better to argue about what makes the game the most interesting.

Take basketball. Adding the 3-point line was certainly unfair to the Goliaths in favor of the Davids (or centers in favor of the guards), yet it opened up the game and made it more interesting. From my own experience in a fledgling sport, paintball has had issues with rate of fire (ROF) caps and guns that ramp (i.e., shoot semi at low ROF, but shoot faster than semi as long as a higher ROF is maintained). The big debate was ramping vs. semi. Ramping leveled the playing field in one sense because everyone could shoot the same speed, however, it helped back guys in favor of front guys initially because the ROF caps were set at 15 balls per second (bps) initially. This shut down movement and made the games far less interesting. Apparently these caps were brought down to 10-13 bps, depending on the league, which is much closer to what the average person can shoot in semi. I bet this has opened up the game and made movement easier, making it more fun to play and, for the sake of TV dollars, interesting to watch(1). I say I bet because I've been out of the sport for a while, so I don't really know.

(1)There's also the safety issue, which is really just a red herring. Look up the insurance stats, paintball is safer than golf and bowling (E.R. visits per 1000 participants).

Comment author: gwern 05 May 2009 03:04:10AM *  3 points [-]

Look up the insurance stats, paintball is safer than golf and bowling (E.R. visits per 1000 participants).

My first reaction is 'well, yeah, just look at who plays paintball versus who plays golf or bowling'. Unless those stats have taken into account the differing ER visit rates of teens & senior citizens, I don't think that says very much about how safe paintball is; teens playing bowling or golf probably have even lower ER visit rates...

Comment deleted 05 May 2009 03:48:07AM [-]
Comment author: CronoDAS 05 May 2009 07:34:15AM 0 points [-]

I suppose the relevant safety measures are to prevent people from getting struck by golf balls?

Comment author: gwern 05 May 2009 04:00:16PM 0 points [-]

Oh no. The safety measures are there for the same reason they are in croquet. If you follow me.

Comment author: Matt_Simpson 05 May 2009 07:11:18PM 0 points [-]

Good point. All three sports (paintball, golf, and bowling) are significantly safer than basketball, baseball, football, hockey, and just about any other sport you can name according to the same stats.

A quick google search brought this up, which is consistent with stats I've seen in the past: http://www.americanpaintballcoliseum.com/new/index.php?option=com_content&task=view&id=13&Itemid=53

Paintball, golf and bowling have under 1 injury per 1000 participants (paintball was lowest with .24) while the other four sports named are in the double digits.

Comment author: orthonormal 05 May 2009 02:27:25AM 2 points [-]

Taking the broader view, I wonder how much complaining about cheats is really an attempt by Goliath to have slings declared unfair.

Reminds me of the Playing to Win essay linked here a few weeks ago.

And how much of the desire to be nice and conform is evolution telling David to fall in line.

That doesn't make sense, though. If playing "cheap" in this way benefits David against Goliath, then evolution would favor a whole lot of Davids playing "cheap".

Comment author: [deleted] 07 May 2009 12:06:21PM *  3 points [-]

The most important part of the article, I think:

"“Eurisko was exposing the fact that any finite set of rules is going to be a very incomplete approximation of reality,” Lenat explained. “What the other entrants were doing was filling in the holes in the rules with real-world, realistic answers. But Eurisko didn’t have that kind of preconception, partly because it didn’t know enough about the world.” So it found solutions that were, as Lenat freely admits, “socially horrifying”: send a thousand defenseless and immobile ships into battle; sink your own ships the moment they get damaged. ".

Lenat, Lawrence, David, and the basketball girls all 'played' in a way that emphasized their own strengths and took advantage of the limits of the situation; they refused to accept the conventions everyone else held, and so they were able to beat them.

Comment author: SoullessAutomaton 05 May 2009 02:33:31AM 3 points [-]

Reminds me of the Playing to Win essay linked here a few weeks ago.

This was my first thought, as well. These "Goliaths" sounds like scrubs who complained loud enough to get favors from the people in charge.

Comment author: [deleted] 05 May 2009 05:54:24PM *  1 point [-]

deleted

Comment author: JulianMorrison 05 May 2009 02:42:32AM 0 points [-]

Not sure what you mean by "cheap".

Comment author: MrHen 05 May 2009 04:41:09AM *  5 points [-]

"Cheap" is a term used in the Playing to Win essays. It generally refers to a tactic that is uninteresting or repetitive but successful.

The example used in the essays is repeating the same move over and over in Street Fighter.

(Edit) The example from Eurisko is that making ships that sink themselves is "cheap" because ships in a real war wouldn't do that. It is a valid strategy according to the rules of the game but invalid according to extraneous rules that have no bearing on the game.

Comment author: Zvi 05 May 2009 08:18:54PM 2 points [-]

In the types of conflicts described David is not fighting on a level playing field. Most of the time Goliath must actively defeat David, Goliath is not allowed to utilize his full power and no matter the cost denying Goliath his aims is considered a victory. Unconventional strategies are no doubt helpful but these are very different from competitions. If anything, I would argue a computer simulation in the Navy competition WAS Goliath!

Comment author: blogospheroid 05 May 2009 05:19:12AM *  -2 points [-]

After thinking a little while about this article, (very well written, btw) I was trying to come up with a counter-example.

I think the complaints that the average left-leaning person has towards entrepreneurs who suceed is also similar to Goliath's complaints in the article.

They socialists know the rules, the economic parameters. Yet somehow, something emerges that is socially horrifying, or in this case horrifying to the person viewing it. And these people end up creating documentaries like the corporation that compare a corporation to a psychopath. The way out is to design a better system. If they are so concerned, let them use half that brain power to design better rules.

however the nice part is that this populism created a backlash effect in this financial crisis where a huge number of people are in favour of the wall-street bankers collapsing, saying "they knew the rules they were playing under. let them collapse. no bailouts"

More to the topic, Marketing warfare by al ries and jack trout details strategies for every level of strength. what to do when u are the leader, when you are level 2, when you are a minnow. etc.

Comment author: MichaelVassar 05 May 2009 06:29:58AM 0 points [-]

Hurray for efficient markets! Hip Hip Hurray! Off hand, sounds like Graham and Dodd investing.
Always works, but too slow and too much work to be fun.