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  • Translator: Joseph Geni Reviewer: Morton Bast

    曾幾何時,

  • Once upon a time

    我們生活在經濟與金融 的增長和繁榮中。

  • we lived in an economy of financial growth and prosperity.

    這就是人們所說的“大穩健”時期,

  • This was called the Great Moderation,

    這種誤導性的看法被大多數經濟學家,

  • the misguided belief by most economists,

    政策制定者以及中央銀行所相信著。

  • policymakers and central banks

    他們深信我們已經演進到一個新時代,

  • that we have transformed into a new world

    一個永不停止增長和永葆繁榮的世界,

  • of never-ending growth and prosperity.

    這個結論是由強健和穩定的GDP增長、

  • This was seen by robust and steady GDP growth,

    受到良好控制的低通貨膨脹率、

  • by low and controlled inflation,

    低失業率,

  • by low unemployment,

    和受控制的低金融波動率而得出的。

  • and controlled and low financial volatility.

    但是2007年和2008年的大衰退,

  • But the Great Recession in 2007 and 2008,

    和大崩盤,打破了這個繁榮假象。

  • the great crash, broke this illusion.

    金融行業損失了數千億美元,

  • A few hundred billion dollars of losses in the financial sector

    整個世界的GDP

  • cascaded into five trillion dollars

    流失了五兆美元,

  • of losses in world GDP

    還有全球股市大概虧損了

  • and almost $30 trillion losses

    30兆美元。

  • in the global stock market.

    因此,人們對大衰退的理解

  • So the understanding of this Great Recession

    是一場完全出乎常理的意外、

  • was that this was completely surprising,

    是突然湧現的危機,

  • this came out of the blue,

    就像是眾神的憤怒一般。

  • this was like the wrath of the gods.

    沒有人有辦法為此負責。

  • There was no responsibility.

    作為對這場危機的反饋,

  • So, as a reflection of this,

    我們成立了金融危機觀測局。

  • we started the Financial Crisis Observatory.

    我們當時要達到的目標

  • We had the goal to diagnose in real time

    是能實時判斷出金融泡沫,

  • financial bubbles

    和預先判斷出它們的臨界點。

  • and identify in advance their critical time.

    具體來說,是什麼架構了 金融觀測台的地基與科學方法呢?

  • What is the underpinning, scientifically, of this financial observatory?

    是我們開發的一個叫“龍王”的理論。

  • We developed a theory called "dragon-kings."

    "龍王理論"代表著各個種類中的

  • Dragon-kings represent extreme events

    極端事件。

  • which are of a class of their own.

    他們是特殊的,也是異常值,

  • They are special. They are outliers.

    他們衍生於某些特殊機制,

  • They are generated by specific mechanisms

    因此是可以預測的

  • that may make them predictable,

    還可能是可控制的。

  • perhaps controllable.

    “龍王理論"考慮到了 金融價格的時間序列,

  • Consider the financial price time series,

    和一支給定的股票,你的最佳股票

  • a given stock, your perfect stock,

    或者一個全球指數

  • or a global index.

    你能看到這些上下起伏的狀況。

  • You have these up-and-downs.

    峰谷法則是一個金融市場 非常好的測量風險工具,

  • A very good measure of the risk of this financial market

    從高峰至低谷呈現著

  • is the peaks-to-valleys that represent

    一個最糟糕的劇情,

  • a worst case scenario

    你在最高點買入,又在最低價賣出。

  • when you bought at the top and sold at the bottom.

    你可以看到統計資料--不同規模的峰谷法則

  • You can look at the statistics, the frequency of the occurrence

    的出現頻率,

  • of peak-to-valleys of different sizes,

    這些都會在表格裡呈現。

  • which is represented in this graph.

    現在有趣的是,99%的

  • Now, interestingly, 99 percent

    不同振幅的峰谷法則

  • of the peak-to-valleys of different amplitudes

    都可以由普通的冪次定律反映出來

  • can be represented by a universal power law

    由這條紅線反映。

  • represented by this red line here.

    更有趣的是,這還是離群值,這些屬於特例。

  • More interestingly, there are outliers, there are exceptions

    在這條紅線之上

  • which are above this red line,

    和那些基於其他99%峰谷法則校準的

  • occur 100 times more frequently, at least,

    所預測會發生的推論相比

  • than the extrapolation would predict them to occur

    發生的頻率

  • based on the calibration of the 99 percent remaining

    至少超過100倍以上。

  • peak-to-valleys.

    這可是個依聯性極強的準則,

  • They are due to trenchant dependancies

    損失的後頭跟著一個損失,

  • such that a loss is followed by a loss

    又接續著另一個損失。

  • which is followed by a loss which is followed by a loss.

    大多標準風險管理工具都遺漏了

  • These kinds of dependencies

    如此露骨的關聯性,

  • are largely missed by standard risk management tools,

    當他們應該留意"龍王"的時候

  • which ignore them and see lizards

    常常是忽略它而只看到一些蜥蜴。

  • when they should see dragon-kings.

    "龍王理論"的根本機制

  • The root mechanism of a dragon-king

    是一項緩慢而走向不穩定的成熟過程

  • is a slow maturation towards instability,

    它就是泡沫,

  • which is the bubble,

    而泡沫的頂點往往被隨破滅的開始。

  • and the climax of the bubble is often the crash.

    這跟用文火燒開水很相似

  • This is similar to the slow heating of water

    在實驗中當試管中的水達到沸點時,

  • in this test tube reaching the boiling point,

    裡頭的水將產生不穩定的狀態,

  • where the instability of the water occurs

    轉變型態為蒸氣相。

  • and you have the phase transition to vapor.

    而這個過程絕非是線性演變,

  • And this process, which is absolutely non-linear --

    故無法透過標準化技術去預測,

  • cannot be predicted by standard techniques --

    這是集體緊急行為的反射,

  • is the reflection of a collective emergent behavior

    是根深蒂固的內在根性。

  • which is fundamentally endogenous.

    所以,泡沫破滅的根源,危機的根源

  • So the cause of the crash, the cause of the crisis

    須從系統內在的不穩定中發覺,

  • has to be found in an inner instability of the system,

    且任何細微的擾動 都會讓這個不穩定現形。

  • and any tiny perturbation will make this instability occur.

    現在你們當中某些人可能已經察覺,

  • Now, some of you may have come to the mind

    這和黑天鵝效應並不相關,

  • that is this not related to the black swan concept

    你經常聽到這個名詞嗎?

  • you have heard about frequently?

    要記得,黑天鵝是稀有的鳥類,

  • Remember, black swan is this rare bird

    那種你才看過一次,便會讓人突然粉碎

  • that you see once and suddenly shattered your belief

    過往"天鵝都該是白色的"那種信念

  • that all swans should be white,

    所以它也囊括著不可預測性、不可獲知性,

  • so it has captured the idea of unpredictability,

    表示那些極端的事件

  • unknowability, that the extreme events

    根本就無法得知。

  • are fundamentally unknowable.

    幾乎沒有什麼能脫離

  • Nothing can be further

    我提出的"龍王理論"範疇,

  • from the dragon-king concept I propose,

    它恰好完全相異於大多數的極端事件,

  • which is exactly the opposite, that most extreme events

    是可獲知且可預測的。

  • are actually knowable and predictable.

    因此我們可以擁有權力並擔起責任

  • So we can be empowered and take responsibility

    去對這些事件進行預測。

  • and make predictions about them.

    現在就讓我的龍王來燒掉黑天鵝吧!

  • So let's have my dragon-king burn this black swan concept.

    (笑聲)

  • (Laughter)

    有很多先期的警報訊號

  • There are many early warning signals

    可以透過這個理論預測。

  • that are predicted by this theory.

    讓我為您舉例說明,

  • Let me just focus on one of them:

    這個超級指數成長伴隨著正向的反饋,

  • the super-exponential growth with positive feedback.

    這是什麼意思呢?

  • What does it mean?

    假想你現在進行一項投資,

  • Imagine you have an investment

    第一年你獲得了百分之五的報酬,

  • that returns the first year five percent,

    第二年百分之十、第三年百分之二十,

  • the second year 10 percent, the third year 20 percent,

    再下一年有百分之四十, 這不是很令人驚奇嗎?

  • the next year 40 percent. Is that not marvelous?

    這就是超級指數成長。

  • This is a super-exponential growth.

    一種標準指數成長,相對於其他增長

  • A standard exponential growth corresponds

    比如說線性增長只維持在百分之十。

  • to a constant growth rate, let's say, of 10 percent

    重點在於,在泡沫化期間重複演變了很多次

  • The point is that, many times during bubbles,

    諸多正回饋在多次演變中產生,

  • there are positive feedbacks which can be of many times,

    過程中到達先前的成長增強幅度

  • such that previous growths enhance,

    再更往前推進,增長到下一個成長級距,

  • push forward, increase the next growth

    直至超級指數成長的程度

  • through this kind of super-exponential growth,

    它是非常強而銳利的,並不是維持穩定發展的,

  • which is very trenchant, not sustainable.

    主要概念是來自於

  • And the key idea is that the mathematical solution

    表現在這類有限時間奇異點模型的數學解法。

  • of this class of models exhibit finite-time singularities,

    意思是在某個臨界時間上,

  • which means that there is a critical time

    它的系統將崩解,改變其體系,

  • where the system will break, will change regime.

    這可能是崩盤,也可能是平穩的,或其他可能

  • It may be a crash. It may be just a plateau, something else.

    關鍵放在臨界時間上。

  • And the key idea is that the critical time,

    在早期發展超級指數成長時,

  • the information about the critical time is contained

    有關臨界時間的資訊是包含在內的。

  • in the early development of this super-exponential growth.

    我們前期將這個理論應用在實驗中,

  • We have applied this theory early on, that was our first success,

    也是我們第一次成功地

  • to the diagnostic of the rupture of key elements

    診斷出鐵火箭破裂的關鍵要素。

  • on the iron rocket.

    我們採用聲發射器這種你可以聽見

  • Using acoustic emission, you know, this little noise

    它發出小小噪音在對著你唱歌的東西。

  • that you hear a structure emit, sing to you

    當它承受壓力,開始顯現損壞時

  • when they are stressed, and reveal the damage going on,

    便產生集體的正回饋現象,

  • there's a collective phenomenon of positive feedback,

    也就是越來越多的損壞會伴隨著更多損壞。

  • the more damage gives the more damage,

    因此你可以在可能的範圍間

  • so you can actually predict,

    去確切的預測

  • within, of course, a probability band,

    它的破裂何時會產生。

  • when the rupture will occur.

    所以現在可以成功地用在

  • So this is now so successful that it is used

    確認飛機[能否]飛行的初期階段。

  • in the initial phase of [unclear] the flight.

    也許更加出奇的是,相同的理論形式

  • Perhaps more surprisingly, the same type of theory

    也能運用在生物學或是醫療上,

  • applies to biology and medicine,

    像是在分娩、生產、癲癬發作時。

  • parturition, the act of giving birth, epileptic seizures.

    從懷孕七個月,母體開始感到

  • From seven months of pregnancy, a mother

    陣陣的子宮收縮前兆,

  • starts to feel episodic precursory contractions of the uterus

    這類顯著朝向不穩定的、

  • that are the sign of these maturations

    將要生下寶寶的成熟過程,

  • toward the instability, giving birth to the baby,

    龍王理論的徵兆。

  • the dragon-king.

    所以假如去測量這些前兆

  • So if you measure the precursor signal,

    就可以預先判斷

  • you can actually identify pre- and post-maturity problems

    事件發生前後的問題。

  • in advance.

    癲癬發作也是有各種不同的形式,

  • Epileptic seizures also come in a large variety of size,

    當大腦進入了超臨界狀態時,

  • and when the brain goes to a super-critical state,

    採用龍王理論能有一定程度的預見,

  • you have dragon-kings which have a degree of predictability

    進而協助病患去處理自身症狀。

  • and this can help the patient to deal with this illness.

    我們已經在許多系統中應用這個理論,

  • We have applied this theory to many systems,

    走山、冰川崩塌,

  • landslides, glacier collapse,

    甚至是成功地預測熱門動態,

  • even to the dynamics of prediction of success:

    像是賣座鉅片、YouTube短片、電影等等。

  • blockbusters, YouTube videos, movies, and so on.

    但或許最重要的應用

  • But perhaps the most important application

    是應用在金融面。

  • is for finance, and this theory

    我相信這個理論闡明了 我們曾經歷過的金融危機,

  • illuminates, I believe, the deep reason

    其深層的原因

  • for the financial crisis that we have gone through.

    根自於三十年的泡沫歷史。

  • This is rooted in 30 years of history of bubbles,

    自1980年起

  • starting in 1980, with the global bubble

    全世界的泡沫在1987年破裂,

  • crashing in 1987,

    接連在後的有其他諸多泡沫,

  • followed by many other bubbles.

    當中最大的叫做2000年的"新經濟"網路泡沫

  • The biggest one was the "new economy" Internet bubble

    在2000年破裂。

  • in 2000, crashing in 2000,

    之後許多國家的房地產泡沫,

  • the real estate bubbles in many countries,

    各處充斥著金融衍生產品泡沫,

  • financial derivative bubbles everywhere,

    股市泡沫也是無所不在,

  • stock market bubbles also everywhere,

    商品與各種泡沫,債務與信貸泡沫---

  • commodity and all bubbles, debt and credit bubbles --

    泡沫,泡沫,泡沫

  • bubbles, bubbles, bubbles.

    我們共有這全球性泡沫,

  • We had a global bubble.

    這是全球市場被高估的程度,

  • This is a measure of global overvaluation

    顯露出我所指的,

  • of all markets, expressing what I call

    一台永久印鈔機的幻覺

  • an illusion of a perpetual money machine

    突然在2007年崩盤了。

  • that suddenly broke in 2007.

    問題在於我們總看到相同的策略,

  • The problem is that we see the same process,

    特別是透過量化寬鬆,

  • in particular through quantitative easing,

    各國政府老想著要永遠打開印鈔機 去解決金融危機

  • of a thinking of a perpetual money machine nowadays

    打從2008年起,

  • to tackle the crisis since 2008 in the U.S., in Europe,

    在美國、歐洲、日本都是。

  • in Japan.

    這有著非常重要的意義

  • This has very important implications

    來幫助我們理解量化寬鬆

  • to understand the failure of quantitative easing

    以及緊縮政策為何會失敗。

  • as well as austerity measures

    除非我們直擊核心,

  • as long as we don't attack the core,

    解決這種永久印刷機的結構性原因。

  • the structural cause of this perpetual money machine thinking.

    這些都是龐大的主張,

  • Now, these are big claims.

    為何你需要相信我呢?

  • Why would you believe me?

    嗯,也許是因為在過去的15年裡

  • Well, perhaps because, in the last 15 years

    我們從象牙塔裡走了出來

  • we have come out of our ivory tower,

    並開始發表了"事前"

  • and started to publish ex ante --

    我強調這個詞"事前",意思指的是"預先"

  • and I stress the term ex ante, it means "in advance" —

    在確認泡沫存在以及金融過剩,

  • before the crash confirmed

    在崩盤以前。

  • the existence of the bubble or the financial excesses.

    這些是近期歷史中,

  • These are a few of the major bubbles

    我們已經歷的一些大型泡沫。

  • that we have lived through in recent history.

    這些泡沫都有其有趣故事。

  • Again, many interesting stories for each of them.

    再一次地,讓我告訴各位其中一兩件

  • Let me tell you just one or two stories

    怎麼處理大規模泡沫的故事。

  • that deal with massive bubbles.

    我們都知道中國奇蹟。

  • We all know the Chinese miracle.

    這是股市的大規模泡沫展示,

  • This is the expression of the stock market

    僅在短短數年間,指數跳漲了三倍,

  • of a massive bubble, a factor of three,

    300%

  • 300 percent in just a few years.

    在2007年的九月,

  • In September 2007,

    我受邀到一個總體對沖基金管理人會議

  • I was invited as a keynote speaker of a macro hedge fund

    去做專題演講。

  • management conference,

    我在會議上做了預測,

  • and I showed to the conference a prediction

    在2007年底前

  • that by the end of 2007, this bubble

    這顆泡沫就會發生質變。

  • would change regime.

    可能是場崩盤,鐵定動盪。

  • There might be a crash. Certainly not sustainable.

    你們相信這群絕頂聰明、積極、

  • Now, how do you believe the very smart,

    又見廣多聞的總體對沖基金經理人們

  • very motivated, very informed macro hedge fund managers

    對這個預測有何反應嗎?

  • reacted to this prediction?

    你們知道嗎,他們直到現在

  • You know, they had made billions

    已經丟下數十億在這棵泡沫上衝浪。

  • just surfing this bubble until now.

    他們對我說: "Didier"

  • They told me, "Didier,

    "是啦,這個市場確實是可能被高估"

  • yeah, the market might be overvalued,

    "但你可能忘了"

  • but you forget something.

    "2008年八月的北京奧運就要來了"

  • There is the Beijing Olympic Games coming

    "顯然地"

  • in August 2008, and it's very clear that

    "中國政府正在控制經濟"

  • the Chinese government is controlling the economy

    "採取一切手段"

  • and doing what it takes

    "也避免任何波動並控制股票市場"

  • to also avoid any wave and control the stock market."

    在我發表完的三週之後

  • Three weeks after my presentation,

    市值就蒸發了百分之二十,

  • the markets lost 20 percent

    在經歷劇烈的波動後,

  • and went through a phase of volatility,

    到了當年年底,

  • upheaval, and a total market loss of

    總市值已經損失了百分之七十。

  • 70 percent until the end of the year.

    我們怎麼會犯下這種集體錯誤?

  • So how can we be so collectively wrong

    怎麼會在發展成 即將轉變、系統已成熟的時候

  • by misreading or ignoring the science

    誤解或是忽略了這樣的科學證據。

  • of the fact that when an instability has developed,

    任何一丁點擾動

  • and the system is ripe, any perturbation

    都會讓其無法控制

  • makes it essentially impossible to control?

    中國市場崩垮了,而後再次復甦

  • The Chinese market collapsed, but it rebounded.

    2009年的時候,我們也辨識出新泡沫。

  • In 2009, we also identified that this new bubble,

    一顆規模略小、不穩定的泡沫。

  • a smaller one, was unsustainable,

    我們就再次"預先地"公開預測

  • so we published again a prediction, in advance,

    到2009年八月前,市場會開始修正

  • stating that by August 2009, the market will correct,

    不會繼續維持現在的軌跡。

  • will not continue on this track.

    批評家讀到這篇預測說

  • Our critics, reading the prediction,

    "不,絕不可能"

  • said, "No, it's not possible.

    "中國政府還在這兒呢!"

  • The Chinese government is there.

    "他們已經學過教訓、中央會控制一切"

  • They have learned their lesson. They will control.

    "他們想從這波成長裡撈些好處"

  • They want to benefit from the growth."

    也許這群批評家 根本沒從之前事件得到教訓。

  • Perhaps <