8 ms·

The Black Swan and the Bell Curve

31 points by pauldelany 15y ago

jannes 15y ago
As a German reader I think I can say that the part about Germany is wrong. In Germany the whole deal is about renewable energy. Even though nuclear energy does not produce greenhouse gasses and seems to be clean, it is by no means a renewable energy source. For most Germans, clean energy is certainly not the goal, but sustainable and renewable energy is. The article totally confuses these two things. Also, a majority of Germans believes that nuclear energy is just too dangerous to be handled by humans. (Yes, we are pussies in this regard.) The commitment to phase out nuclear energy does not mean to be less commited to the reduction of greenhouse gas emissions. In fact it only means that you have to be more focussed on your goals than before. Personally, I heavily doubt that the cut of 40% in greenhouse gas emissions until 2020 (compared to the level of 1990) will work out. But it is nevertheless good to have these ambitious goals. They have probably led to better legislation to encourage the use of renewable energy than in other countries. On some level these goals put pressure on politicians to do something. If they lead to only 5% reduction, I would already consider it a success. If that scale for success seems stupid to you, you are right. But this is the measurement of success I put on politicians. I don't expect much from them. That's what I learned from the past. Most of them can only think until the next election. 2020 is just too distant to be important for most politicians.
- oelewapperke 15y ago
  Well, it seems it is a fact that this guy can calculate, and you have neglected your homework. A nuclear phase-out means that Germany needs to build 25 GIGAwatt of baseload power (that means 75 gigawatt of renewable day-only energy + an energy storage facility that makes a nuclear power plant look like a duracell battery). So your own institutions have calculated that power-related CO2 emissions will double as the result of nuclear phase-out. That seems reasonable ... Democracies don't deal well with consequences. A leading to B does not prevent voting for A and against B. But the case is simple : ceasing nuclear means giving up the fight against global warming for 20 years. You're government has ceased the fight against global warming, and this guy is not happy about it. Your argument is dependent on the idea that you can be both, in the short, mid, and long-term. But working to prevent global warming means being pro-nuclear for now (for at least another 10-20 years). Your "scale for success" is going to screw up both initiatives. "Perfect is the enemy of good" - Voltaire
glenra 15y ago
Wow, that author is a truly committed doom-and-gloomer. If I were one too, I'm sure I'd find his argument persuasive. But apparently I'm wearing the wrong colored glasses to perceive his alleged "plague of violent and weird weather in the last few years" as evidence of more than selective attention and status quo bias.
- leot 15y ago
  He's not perceiving any particular weird weather events as evidence for climate change -- we won't know for some time whether the freaky weather is or isn't evidence climate change related because the data are so noisy. That said, in general, extreme weather has been predicted by climate change models[1]. If your neighbor said to you "looks like it's going to rain tomorrow night -- I saw a storm system coming in while I was out of town", and then tomorrow night it rains, you don't say "well, Fred, you predicted it, but we don't know for sure that the rain was caused by the storm you saw, so we're going to be sure we take everything we hear from you with a grain of salt." The author wasn't saying "the rain was caused by the storm Fred saw". Rather, he's saying that no one is listening to Fred even though the freaky weather suggests that he's been right so far. [1] http://www.nicholas.duke.edu/news/increasingly-variable-summer-rainfall-in-southeast-linked-to-climate-change http://www.nicholas.duke.edu/news/increasingly-variable-summ...
  - glenra 15y ago
    The weather so far isn't freaky. One can say the weather thus far "is consistent with" predictions mostly because the uncertainty bands are wide enough that any weather would be "consistent with" predictions. This author is claiming weather is somehow, shall we say, unusually unusual (and also unusually bad); but it just isn't so. Take flooding, for example. Yes, there have been some bad floods recently but no, flooding isn't unusually bad. Quote: "Despite common perception, in general, the detected trends are more negative (less intense floods in most recent years) than positive. Similarly, Svensson et al. (2005) and Di Baldassarre et al. (2010) did not find systematical change neither in flood increasing or decreasing numbers nor change in flood magnitudes in their analysis." http://rogerpielkejr.blogspot.com/2011/04/decrease-in-floods-around-world.html http://rogerpielkejr.blogspot.com/2011/04/decrease-in-floods... The weather so far suggests the people claiming doom and gloom is already happening have been wrong so far. Certainly one can find what looks like evidence to the contrary by cherry-picking - just find specific places where specific types of weather extremes happened to get "more extreme" over the period for which you've got good data, then write an article like the one you link to. Ask yourself this: If they had looked at some different region and found it to have a trend towards less extreme weather or to have no trend at all, would this finding have been publishable? Could they have gotten press for saying "we looked at all the natural causes we could think of, ruled them out, and are forced to conclude that AGW made for less extreme weather in (area X)"? If not, there's a publication bias such that we'd see regular "it's getting worse" articles even if it were not, in fact, getting worse.
jswinghammer 15y ago
A Black Swan in this context would be a shock to the system that no one saw coming nor could see coming. For instance a change in the sun which would drastically warm or cool the earth far beyond the effects of CO2. Maybe a natural disaster or an industrial accident that had a cascade effect that would reach beyond what anyone could have seen coming. You can't do anything about either of these things but that won't stop people from suggesting it could have been avoided with the right (or more of): "fill in the blank with your favorite solution to all problems in life."
- leot 15y ago
  Not entirely -- it's better to think of "unknown unknowns" that current circumstances might well contribute to the probability of occurring. We might know of 10 events that all "only" have a 1% chance of occurring, causing us to estimate risk of any one occurring at 10%. But because of how much everything is getting mucked with, there might not be 10 events that have a 1% chance, but instead 50, or 100.
nice1 15y ago
What a load of bullsh^t ...
Yhippa 15y ago
I think the author might be misinterpreting The Black Swan Theory when he says this: " . . . Nassim Nicholas Taleb and Benoit Mandelbrot postulate that seemingly very improbable events take place because the probability distribution turns out (mainly in hindsight!) to have "fat tails"--that is, instead of conforming to the "normal" Bell Shape form, the distribution has a shape in which the probability of extreme events is greater than normal." I think what NNT is trying to say is not that the probability of the tails extreme events is greater than normal but rather that these Black Swan events are rare and we tend not to predict them due to our bell curve obsession. When they do happen however they're game-changers.
- leot 15y ago
  No. The consequence of fat tails is that the risk-reward relationship becomes extremely wonky. Assuming that the actors involved were rational, both the BP disaster and the housing market crashes could be characterized as the result of a mis-application of the normal distribution to distributions that actually had fat tails. BP management _way_ underestimated the risk of an extremely costly crisis, as did housing speculators.
- NY_USA_Hacker 15y ago
  The article is junk: E.g., it confuses 'normal' as in usual and 'normal' as in the Gaussian distribution. And 'fat tails' is not nearly specific enough to describe the exceptional or disastrous events of 'black swans'. The just isn't serious and should be ignored.
NY_USA_Hacker 15y ago
Yes, during the campaign, Chosen of Oprah, Blessed Be He, promised to ratchet up regulations to shut down the coal fired electric power plants. But that's now too little, too late because as we know: (1) Humans are evil. They are sinful, greedy, duplicitous, violent, irrational, and destructive. The claims that the concerns about human caused significant global warming are just a flim flam fraud are just deceptions of the Devil. (2) Evil humans are destroying the planet, the 100% all-natural, delicate, sensitive, pure, pristine, precious environment. The weather was never like this before evil humans started working with the bow and arrow. (3) For this evil transgression, humans will be made to suffer terrible retribution of extreme weather, failed crops, farms and forests turned into deserts, lowlands flooded, cute, cuddly, sweet, pure white baby polar bears drowning in the ice-free Arctic, penguins starving, and worse. The whales will die, and when the whales die, the oceans will die and then we will die, and the whales are starting to die. (4) For this retribution, humans need redemption or death from their sin, evil, and transgressions. The only possible redemption is sacrifice. We have to start by giving up computers, telephones, airplanes, plastics, TV, yes, even including the soaps, electric power, cars, frozen foods, and McDonald's French fries. Then we must give up synthetic fabrics, permanent press, washing machines, paper plates, deodorant, and women's bras and panties. Humans must abstain from sex. But this will not be enough, not nearly enough: The sun is about to stop moving across the sky, and the only solution is to have a holy Mayan priest hold ceremonies pouring the blood of evil humans on a sacred rock. The only qualified priest is Saint Laureate Al Guru aided by the dedicated, devoted Guru Acolytes lead by Sister Laurie. The blood will come from sacrificing virgins (when they first arrived at the ceremony with Saint Guru). Only in this way, along with Cap and Trade and the EPA, can the planet be saved.
- leot 15y ago
  Are you saying that global warming isn't real? Are you suggesting that humans aren't responsible? Because if so, you're Just Plain Wrong http://en.wikipedia.org/wiki/Global_warming http://en.wikipedia.org/wiki/Global_warming For some reason, millions of people believe that scientists, who spend all day trying to prove each other wrong, have been conspiring to lie about global warming. At the same time, those millions ignore the actual organized disinformation campaign perpetrated by those whose businesses get hurt whenever people start conserving fuel.

31 points by pauldelany 15y ago

As a German reader I think I can say that the part about Germany is wrong. In Germany the whole deal is about renewable energy. Even though nuclear energy does not produce greenhouse gasses and seems to be clean, it is by no means a renewable energy source. For most Germans, clean energy is certainly not the goal, but sustainable and renewable energy is. The article totally confuses these two things. Also, a majority of Germans believes that nuclear energy is just too dangerous to be handled by humans. (Yes, we are pussies in this regard.) The commitment to phase out nuclear energy does not mean to be less commited to the reduction of greenhouse gas emissions. In fact it only means that you have to be more focussed on your goals than before. Personally, I heavily doubt that the cut of 40% in greenhouse gas emissions until 2020 (compared to the level of 1990) will work out. But it is nevertheless good to have these ambitious goals. They have probably led to better legislation to encourage the use of renewable energy than in other countries. On some level these goals put pressure on politicians to do something. If they lead to only 5% reduction, I would already consider it a success. If that scale for success seems stupid to you, you are right. But this is the measurement of success I put on politicians. I don't expect much from them. That's what I learned from the past. Most of them can only think until the next election. 2020 is just too distant to be important for most politicians.

oelewapperke 15y ago
Well, it seems it is a fact that this guy can calculate, and you have neglected your homework. A nuclear phase-out means that Germany needs to build 25 GIGAwatt of baseload power (that means 75 gigawatt of renewable day-only energy + an energy storage facility that makes a nuclear power plant look like a duracell battery). So your own institutions have calculated that power-related CO2 emissions will double as the result of nuclear phase-out. That seems reasonable ... Democracies don't deal well with consequences. A leading to B does not prevent voting for A and against B. But the case is simple : ceasing nuclear means giving up the fight against global warming for 20 years. You're government has ceased the fight against global warming, and this guy is not happy about it. Your argument is dependent on the idea that you can be both, in the short, mid, and long-term. But working to prevent global warming means being pro-nuclear for now (for at least another 10-20 years). Your "scale for success" is going to screw up both initiatives. "Perfect is the enemy of good" - Voltaire

glenra 15y ago

Wow, that author is a truly committed doom-and-gloomer. If I were one too, I'm sure I'd find his argument persuasive. But apparently I'm wearing the wrong colored glasses to perceive his alleged "plague of violent and weird weather in the last few years" as evidence of more than selective attention and status quo bias.

leot 15y ago
He's not perceiving any particular weird weather events as evidence for climate change -- we won't know for some time whether the freaky weather is or isn't evidence climate change related because the data are so noisy. That said, in general, extreme weather has been predicted by climate change models[1]. If your neighbor said to you "looks like it's going to rain tomorrow night -- I saw a storm system coming in while I was out of town", and then tomorrow night it rains, you don't say "well, Fred, you predicted it, but we don't know for sure that the rain was caused by the storm you saw, so we're going to be sure we take everything we hear from you with a grain of salt." The author wasn't saying "the rain was caused by the storm Fred saw". Rather, he's saying that no one is listening to Fred even though the freaky weather suggests that he's been right so far. [1] http://www.nicholas.duke.edu/news/increasingly-variable-summer-rainfall-in-southeast-linked-to-climate-change http://www.nicholas.duke.edu/news/increasingly-variable-summ...
- glenra 15y ago
  The weather so far isn't freaky. One can say the weather thus far "is consistent with" predictions mostly because the uncertainty bands are wide enough that any weather would be "consistent with" predictions. This author is claiming weather is somehow, shall we say, unusually unusual (and also unusually bad); but it just isn't so. Take flooding, for example. Yes, there have been some bad floods recently but no, flooding isn't unusually bad. Quote: "Despite common perception, in general, the detected trends are more negative (less intense floods in most recent years) than positive. Similarly, Svensson et al. (2005) and Di Baldassarre et al. (2010) did not find systematical change neither in flood increasing or decreasing numbers nor change in flood magnitudes in their analysis." http://rogerpielkejr.blogspot.com/2011/04/decrease-in-floods-around-world.html http://rogerpielkejr.blogspot.com/2011/04/decrease-in-floods... The weather so far suggests the people claiming doom and gloom is already happening have been wrong so far. Certainly one can find what looks like evidence to the contrary by cherry-picking - just find specific places where specific types of weather extremes happened to get "more extreme" over the period for which you've got good data, then write an article like the one you link to. Ask yourself this: If they had looked at some different region and found it to have a trend towards less extreme weather or to have no trend at all, would this finding have been publishable? Could they have gotten press for saying "we looked at all the natural causes we could think of, ruled them out, and are forced to conclude that AGW made for less extreme weather in (area X)"? If not, there's a publication bias such that we'd see regular "it's getting worse" articles even if it were not, in fact, getting worse.

jswinghammer 15y ago

A Black Swan in this context would be a shock to the system that no one saw coming nor could see coming. For instance a change in the sun which would drastically warm or cool the earth far beyond the effects of CO2. Maybe a natural disaster or an industrial accident that had a cascade effect that would reach beyond what anyone could have seen coming. You can't do anything about either of these things but that won't stop people from suggesting it could have been avoided with the right (or more of): "fill in the blank with your favorite solution to all problems in life."

leot 15y ago
Not entirely -- it's better to think of "unknown unknowns" that current circumstances might well contribute to the probability of occurring. We might know of 10 events that all "only" have a 1% chance of occurring, causing us to estimate risk of any one occurring at 10%. But because of how much everything is getting mucked with, there might not be 10 events that have a 1% chance, but instead 50, or 100.

nice1 15y ago

What a load of bullsh^t ...

Yhippa 15y ago

I think the author might be misinterpreting The Black Swan Theory when he says this: " . . . Nassim Nicholas Taleb and Benoit Mandelbrot postulate that seemingly very improbable events take place because the probability distribution turns out (mainly in hindsight!) to have "fat tails"--that is, instead of conforming to the "normal" Bell Shape form, the distribution has a shape in which the probability of extreme events is greater than normal." I think what NNT is trying to say is not that the probability of the tails extreme events is greater than normal but rather that these Black Swan events are rare and we tend not to predict them due to our bell curve obsession. When they do happen however they're game-changers.

leot 15y ago
No. The consequence of fat tails is that the risk-reward relationship becomes extremely wonky. Assuming that the actors involved were rational, both the BP disaster and the housing market crashes could be characterized as the result of a mis-application of the normal distribution to distributions that actually had fat tails. BP management _way_ underestimated the risk of an extremely costly crisis, as did housing speculators.
NY_USA_Hacker 15y ago
The article is junk: E.g., it confuses 'normal' as in usual and 'normal' as in the Gaussian distribution. And 'fat tails' is not nearly specific enough to describe the exceptional or disastrous events of 'black swans'. The just isn't serious and should be ignored.

NY_USA_Hacker 15y ago

Yes, during the campaign, Chosen of Oprah, Blessed Be He, promised to ratchet up regulations to shut down the coal fired electric power plants. But that's now too little, too late because as we know: (1) Humans are evil. They are sinful, greedy, duplicitous, violent, irrational, and destructive. The claims that the concerns about human caused significant global warming are just a flim flam fraud are just deceptions of the Devil. (2) Evil humans are destroying the planet, the 100% all-natural, delicate, sensitive, pure, pristine, precious environment. The weather was never like this before evil humans started working with the bow and arrow. (3) For this evil transgression, humans will be made to suffer terrible retribution of extreme weather, failed crops, farms and forests turned into deserts, lowlands flooded, cute, cuddly, sweet, pure white baby polar bears drowning in the ice-free Arctic, penguins starving, and worse. The whales will die, and when the whales die, the oceans will die and then we will die, and the whales are starting to die. (4) For this retribution, humans need redemption or death from their sin, evil, and transgressions. The only possible redemption is sacrifice. We have to start by giving up computers, telephones, airplanes, plastics, TV, yes, even including the soaps, electric power, cars, frozen foods, and McDonald's French fries. Then we must give up synthetic fabrics, permanent press, washing machines, paper plates, deodorant, and women's bras and panties. Humans must abstain from sex. But this will not be enough, not nearly enough: The sun is about to stop moving across the sky, and the only solution is to have a holy Mayan priest hold ceremonies pouring the blood of evil humans on a sacred rock. The only qualified priest is Saint Laureate Al Guru aided by the dedicated, devoted Guru Acolytes lead by Sister Laurie. The blood will come from sacrificing virgins (when they first arrived at the ceremony with Saint Guru). Only in this way, along with Cap and Trade and the EPA, can the planet be saved.

leot 15y ago
Are you saying that global warming isn't real? Are you suggesting that humans aren't responsible? Because if so, you're Just Plain Wrong http://en.wikipedia.org/wiki/Global_warming http://en.wikipedia.org/wiki/Global_warming For some reason, millions of people believe that scientists, who spend all day trying to prove each other wrong, have been conspiring to lie about global warming. At the same time, those millions ignore the actual organized disinformation campaign perpetrated by those whose businesses get hurt whenever people start conserving fuel.