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A Better Crystal Ball?

foreignaffairs.com

11–20 of 51 posts

Re: A Better Crystal Ball?

#11

This is the most dangerously stupid thing I've ever heard. Tetlock is a known academic charlatan pushing his absolutely useless "superforecasting" nonsense which @nntaleb keeps debunking on Twitter. If Tetlock and friends are so good about forecasting the future, why didn't they predict and warn us about COVID-19 BEFORE @nntaleb and friends (including myself) did? P.S. I have been downvoted for saying this.

Taleb has anecdotes and insults.

Tetlock has data piled on data.

Re: A Better Crystal Ball?

#12
post #8

> Well-calibrated forecasters, for instance, can estimate the likelihood that a skirmish with the Chinese navy in the South China Sea will result in at least two American deaths by December 31. But what policymakers really want to know is the extent to which China will threaten U.S. interests in the coming years and decades. This has never happened (a skirmish, let alone deaths) so how can we think that the forecaste…

> Because they predicted other, different, stuff?

In fact, yes. Prediction is a skill, skills can be developed and different predictors will have varying levels of skillfulness.

The biggest contributor IIRC is Fermi-ization: the skill of decomposing big hard predictions into many smaller predictions.

For example: what are the components of the question? They might include:

- The likelihood of deaths due to combat action. That can in turn include predictions of the relative effects of ship armour, weapons effectiveness, preparedness for combat conditions and so on.

- The number of people involved. If a skirmish involves a hundred ships on each side, 2 deaths is a very low estimate. How many ships are in the area? How many could reach it by December 31st? How many would be likely to be sent?

- The causes of conflict. What are the triggering events, and how likely are they to occur?

I'm sure smarter and better-qualified folks than me can argue all the details, but that's the point. You don't accept the question as a coin-flip with no priors. You go prior-hunting.

Re: A Better Crystal Ball?

#13
Odd to see an article about forecasting without mentioning DeMesquita and Smith's predictioneer models and stakeholder salience models. Also without Charlie Munger's comments on incentives, which have had a better track record than pretty much anyone.

There was much point scoring done after the 2016 U.S. election about polling and predictions being wrong, particularly against Fivethirtyeight, but where I think critics got it wrong was, when someone says there's a %95 chance of an event going in one way, it's not valuable as a prediction, but it certainly is as an accurate assessment of the impact of the results. In 2016, if you told people that the %95 implied probability of winning translated to what felt like paying out a 19/1 loss, a lot of people would have agreed with you.

You can reliably bet on the effect of the upset being inversely proportional to the predicted probabilities. When I see election predictions that are 60:40 I think the 2nd order impacts of the result will be slightly lopsided, but within the realms of expectations. In this sense, %54 chance of winning close races may be better for stability than perceived polarized %95 ones because of how people perceive the results of a loss.

Re: A Better Crystal Ball?

#14

This is the most dangerously stupid thing I've ever heard. Tetlock is a known academic charlatan pushing his absolutely useless "superforecasting" nonsense which @nntaleb keeps debunking on Twitter. If Tetlock and friends are so good about forecasting the future, why didn't they predict and warn us about COVID-19 BEFORE @nntaleb and friends (including myself) did? P.S. I have been downvoted for saying this.

When did anyone predict COVID? You can just throw around assertions that someone predicted something like COVID without providing evidence and expect people to make judgements on it.

Re: A Better Crystal Ball?

#15

Odd to see an article about forecasting without mentioning DeMesquita and Smith's predictioneer models and stakeholder salience models. Also without Charlie Munger's comments on incentives, which have had a better track record than pretty much anyone. There was much point scoring done after the 2016 U.S. election about polling and predictions being wrong, particularly against Fivethirtyeight, but where I think critic…

What's described here is more of a framework than an exact forecasting method. DeMesquita's methods would fit quite well, actually.

> You can reliably bet on the effect of the upset being inversely proportional to the predicted probabilities.

Broadly, yes, if you think of it in an information-theoretic sense. Rare signals carry more information than common ones.

Re: A Better Crystal Ball?

#16
post #6

Earlier quoted context omitted.

They would actually argue the same thing. Certain events are impossible to predict. Other events are not. That’s part of the beauty of the problem. You need to be able to pick the right events to predict and ensure the event is well-defined enough to actually test. Your own examples of why this wouldn’t work are exactly what they discuss as the problem... Eventually a lot of forecasts are correct; what governments, c…

Show me the money: did they warn about COVID-19 way BEFORE it be came a problem, or did they not? If not, why should we take them seriously? It is easy to prognosticate AFTER the fact.

This argument relies on the nirvana fallacy. "You are not perfectly clairvoyant, therefore prediction is worthless".

I recall, but cannot locate, that questions related to the outbreak of trans-species respiratory illnesses from China have been canvassed in the past. It does appear that the US intelligence community expected a pandemic to emerge: https://www.mercurynews.com/2020/03/16/analysis-yes-people-d...

Re: A Better Crystal Ball?

#17
post #8

> Well-calibrated forecasters, for instance, can estimate the likelihood that a skirmish with the Chinese navy in the South China Sea will result in at least two American deaths by December 31. But what policymakers really want to know is the extent to which China will threaten U.S. interests in the coming years and decades. This has never happened (a skirmish, let alone deaths) so how can we think that the forecaste…

> Because they predicted other, different, stuff? In fact, yes. Prediction is a skill, skills can be developed and different predictors will have varying levels of skillfulness. The biggest contributor IIRC is Fermi-ization: the skill of decomposing big hard predictions into many smaller predictions. For example: what are the components of the question? They might include: - The likelihood of deaths due to combat act…

The other big component is using Bayesian inference. For that you need a prior. What's the prior for this? You could look at incidents the US has had in similar freedom of navigation actions, what China has done with other countries, or other similar situations. For example, I can only think of a few similar incidents, and none that escalated to fatalities at sea. So your prior would probably be pretty small, say 1%. After that you would adjust according to new data. For example, China seems willing to do more risky stuff lately, with India being a perfect example. You might raise your estimate based on that. So maybe that raises your estimate to 2%. But it probably shouldn't completely alter your estimate.

Re: A Better Crystal Ball?

#18

This is the most dangerously stupid thing I've ever heard. Tetlock is a known academic charlatan pushing his absolutely useless "superforecasting" nonsense which @nntaleb keeps debunking on Twitter. If Tetlock and friends are so good about forecasting the future, why didn't they predict and warn us about COVID-19 BEFORE @nntaleb and friends (including myself) did? P.S. I have been downvoted for saying this.

You could be right, but I've people-watched on Twitter long enough to know that "person who insults those he disagrees with while name-dropping @nntaleb" is an entire PERSONALITY, one that I take approximately 0% seriously.

Re: A Better Crystal Ball?

#19
A travesty that the U.S. pays over a trillion dollars a year while hosting soldiers in 70 countries...

You would think with that much planning we would have paid attention to experts decades ago warning that we needed more charged fiber (N95) in storage in case of a pandemic at a cost of ~0.0001 trillion ...

Re: A Better Crystal Ball?

#20
post #14

This is the most dangerously stupid thing I've ever heard. Tetlock is a known academic charlatan pushing his absolutely useless "superforecasting" nonsense which @nntaleb keeps debunking on Twitter. If Tetlock and friends are so good about forecasting the future, why didn't they predict and warn us about COVID-19 BEFORE @nntaleb and friends (including myself) did? P.S. I have been downvoted for saying this.

When did anyone predict COVID? You can just throw around assertions that someone predicted something like COVID without providing evidence and expect people to make judgements on it.

Predicted by experts:

https://www.nationalgeographic.com/science/2020/04/experts-w...

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