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Goodhart's Law: When a measure becomes a target, it ceases to be a good measure

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Re: Goodhart's Law: When a measure becomes a target, it ceases to be a good measure

#101

Post by njarboe »

nkoren wrote: post #74
njarboe wrote: post #64

Earlier quoted context omitted.

I would say the complexity is in balancing profit over time. Here is your contradictory force. In the end that large engineering consultancy was making zero profit and was worth nothing. Whether running a business into the ground will give you more overall profit than just selling it and putting the money into government bonds is something one can consider, but in your case was the consultancy owned by the people mak…

> in your case was the consultancy owned by the people making these short-term profit maximizing decisions[?] It was a publicly-listed company, so that'd be a yes. Profit is obviously over time a necessary condition for making a sustainable business. But it's definitely not a sufficient condition. I think there are a huge number of people who don't understand this. Eg.: when I see people clambering for TSLA to make a…

>> in your case was the consultancy owned by the people making these short-term profit maximizing decisions[?] >It was a publicly-listed company, so that'd be a yes.

I'm a bit confused. I stated that public companies are not often owned by the people who mange them and that is a real problem. You are asserting that all publicly-listed companies are managed by their owners. That is just wrong. I own both TSLA and AMZN and of course there are hundreds of things that need to be done to make a sustainable business. Just talking past each other at this point, I think.

Re: Goodhart's Law: When a measure becomes a target, it ceases to be a good measure

#102

Post by stcredzero »

mikeash wrote: post #81
sonnyblarney wrote: post #61

Earlier quoted context omitted.

"If “progress” means murdering civilians by the thousand as part of a vain attempt to maintain a vestige of colonialism, count me out." Progress was defeating a ruthless and murderous North Korean Communist regime who, upon victory, mass murdered 10's of thousands of their own citizens, put 100's of thousands in concentration camps and ruthless oppressed their population for decades. My homework partner in high schoo…

Maybe if the natives hadn’t had to spend decades struggling for independence against various colonial powers, they would have been nicer after they won. I’d like to point out that our allies in that war did all that stuff too, and there’s no reason to think they would have been much nicer if they had won. Part of why they lost is that they alientated much of the population by being oppressive and murderous.

Maybe if the natives hadn’t had to spend decades struggling for independence against various colonial powers, they would have been nicer after they won.

The way it was portrayed in Ken Burns' "The Vietnam War," Ho Chi Minh was an admirer of the US, and would have become an ally, if the US hadn't decided to wholly back France in preserving its colonial interest.

Re: Goodhart's Law: When a measure becomes a target, it ceases to be a good measure

#103

Post by stcredzero »

sonnyblarney wrote: post #88
ranger207 wrote: post #78

Earlier quoted context omitted.

>The US handily won the Vietnam war, full stop. >In classical terms is was a clear and unambiguous outright victory. The only measure of success is whether or not you accomplish your objectives. The US did not accomplish its objectives in Vietnam of keeping a US-friendly government in power. Regardless of tactical measures of success, the US failed in its strategic objectives. I agree that popular culture has not acc…

" The US did not accomplish its objectives in Vietnam of keeping a US-friendly government in power" Yes. They did. While there was conflict. Then they left, and effectively abandoned those objectives. When the North Vietnamese rebuilt it's army and re-invaded the South - propping up the S. Vietnamese government was obviously no longer a military objective, and barely a political one. So the US won a war, withdrew, an…

So the US won a war, withdrew, and then abandoned their ally.

Which is crazy.

Sounds an awful lot like our government was gaming their "target" just to say they achieved it, even though hitting the target wasn't in everyone's best interests.

Re: Goodhart's Law: When a measure becomes a target, it ceases to be a good measure

#104

Post by stcredzero »

refurb wrote: post #99
philipkglass wrote: post #96

Earlier quoted context omitted.

If the North didn't have a capable fighting force any more, and still overwhelmed the South shortly after the US withdrew, that means the US did not actually establish a "a viable and increasingly democratic society" during the time it had a military presence there. Societal viability includes, at a minimum, being able to survive one's enemies. Enemies that were already drastically weakened during the period of US in…

Societal viability includes, at a minimum, being able to survive one's enemies. By that argument, all of western Europe didn't save a viable society since Germany was able to defeat them. I don't agree with that.

By that argument, all of western Europe didn't save a viable society since Germany was able to defeat them.

France had a credible defense. Also, France certainly survived their enemy in the long term.

Re: Goodhart's Law: When a measure becomes a target, it ceases to be a good measure

#105

Post by pmichaud »

njarboe wrote: post #34

The breaking of this law when one uses profit as the measure of a successful company or business is why I think that a well set up market system actually works. People and companies can set up making a profit as their target and it is still a good measure of success, because it is actually what you want. The key for a good society is regulating the places where making max profits can induce bad behavior and leaving a…

I think you're not trolling, but I'm not sure.

The first thing anyone smart does when they make a metric is think about what rules or other measures have to be in place to prevent obvious gaming of the metric to the detriment of the real goal.

When this is done at scale to markets it's called "regulations."

Markets are not even a little Goodhart proof.

Re: Goodhart's Law: When a measure becomes a target, it ceases to be a good measure

#106

Post by legulere »

njarboe wrote: post #34

The breaking of this law when one uses profit as the measure of a successful company or business is why I think that a well set up market system actually works. People and companies can set up making a profit as their target and it is still a good measure of success, because it is actually what you want. The key for a good society is regulating the places where making max profits can induce bad behavior and leaving a…

Many companies don't optimize for profit but optimize for market share and try to be around net zero, the best example being Amazon.

Re: Goodhart's Law: When a measure becomes a target, it ceases to be a good measure

#107

Post by stcredzero »

sonnyblarney wrote: post #84
Semirhage wrote: post #68

Earlier quoted context omitted.

“Progress was defeating a ruthless and murderous North Korean Communist regime...” “Who, upon victory , mass murdered 10's of thousands of their own citizens...” Proofread! Or at the very least, try not to include outright contradictions in your outlandish claims. Claiming that the US won in one sentence, and in the very next declaring the opposite is baffling.

I'm not making any contradictions. The Americans defeated the Viet Kong insurgency and the North Vietnamese, and then withdrew shortly thereafter. After a few years, the North Vietnamese were able to rebuild their Army. They invaded and toppled South Vietnam. Again, my point: people don't seem to have any idea of what actually happened.

I think Goodhart's law gives us a good insight. If the actual goal was to ensure the long term viability of a democratic South Vietnam, the endeavor failed. So what happened, is that the US government "gamed" it by targeting "Body Count" and "winning all the battles." In doing so, it failed to achieve the actual goal in its long term interest.

Re: Goodhart's Law: When a measure becomes a target, it ceases to be a good measure

#108

Post by tlarkworthy »

This is also demonstrated quite well in machine learning with the test set. The target is test error, but you don't let algorithms optimize that directly and instead they optimize against training error. Goodhart's law is a manifestation of over-fitting in social systems.

Re: Goodhart's Law: When a measure becomes a target, it ceases to be a good measure

#109

Post by defen »

waltherg wrote: post #76
davidmanheim wrote: post #27

This is probably where I should mention my two longer articles that discuss this in depth; https://www.ribbonfarm.com/2016/06/09/goodharts-law-and-why-... https://www.ribbonfarm.com/2016/09/29/soft-bias-of-underspec... As well as my more recent paper categorizing the different ways it occurs; https://arxiv.org/abs/1803.04585

Since you’re here, what does the following property stand for in your second paper? s ∈ AifM(s)/gec

Not OP but that should probably render as: s ∈ A if M(s) >= c

So: s (system state) is a member of A (permissible region) if M(s) (proxy measure of s since we can't directly observe it) is greater than or equal to c (threshold)

Re: Goodhart's Law: When a measure becomes a target, it ceases to be a good measure

#110

Post by nkoren »

njarboe wrote: post #101
nkoren wrote: post #74

Earlier quoted context omitted.

> in your case was the consultancy owned by the people making these short-term profit maximizing decisions[?] It was a publicly-listed company, so that'd be a yes. Profit is obviously over time a necessary condition for making a sustainable business. But it's definitely not a sufficient condition. I think there are a huge number of people who don't understand this. Eg.: when I see people clambering for TSLA to make a…

>> in your case was the consultancy owned by the people making these short-term profit maximizing decisions[?] >It was a publicly-listed company, so that'd be a yes. I'm a bit confused. I stated that public companies are not often owned by the people who mange them and that is a real problem. You are asserting that all publicly-listed companies are managed by their owners. That is just wrong. I own both TSLA and AMZN…

Ah, sorry, you're correct. The company was owned by people who wanted short-term profit maximising decisions (its shareholders). The people actually making the decisions also owned shares, but nowhere near a controlling interest.

Anyhow, I agree with your point about companies that are controlled by founders (whether public or not). A (sufficiently pragmatic) visionary with a controlling interest can achieve things that no amount shareholder-focused governance can. Of course they can also drive a company into the ground faster than anyone -- but the heights are reserved for them.

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