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他自己詮釋,這理論挑戰古典經濟學理論中的「理性預期學派」。後者的假設是,人 們針對某個經濟現象(例如市場價格)會給予理性的預期,他們會盡可能、並充分利用所得到的資訊來行動,而不會犯下系統性的錯誤;因此,平均來看,人們的預 期應該是準確的,市場會達到均衡。索羅斯認為,這種認為「金融市場總是朝向均衡發展的理論,不但錯誤而且導致誤解。

反 射理論的前提即是:「我們對這個世界的理解,天生就是不完美的。」因為人們的思考有兩個層次,「一方面,他們尋求去了解自己的處境,我稱之為認知功能;另 一方面,他們嘗試改變自己的處境,我稱之為操縱功能。這兩項功能在某些情況下,他們會相互干擾,我稱之為反射。」從大腦功能來看,人們認為自己了解的投資 環境是「真實」,但實際上,這只是經過大腦合理化後的「真實」。而大腦對世界的理解並不完美,所以我們感受到的只是自以為的「真實」,然後根據自以為的 「真實」下決定。

換 言之,我們必須要了解,自己的決定,其實都是被不完美的理解所影響;對應到投資市場上,這個不完美的預期,也將影響市場的走向。多空循環,是人們對趨勢傳 統的認知,其趨勢的形成是緩步加速、到達高點,然後再緩步下滑,過程像一個對稱的鐘型曲線。但索羅斯認為,因為有投資人的預期心理,導致趨勢形成過程經常 是不對稱的,通常先緩步加速、到達高點,然後急速反轉。

Reflexivity is discordant with equilibrium theory, which stipulates that markets move towards equilibrium and that non-equilibrium fluctuations are merely random noise that will soon be corrected. In equilibrium theory, prices in the long run at equilibrium reflect the underlying fundamentals, which are unaffected by prices. Reflexivity asserts that prices do in fact influence the fundamentals and that these newly-influenced set of fundamentals then proceed to change expectations, thus influencing prices; the process continues in a self-reinforcing pattern. Because the pattern is self-reinforcing, markets tend towards disequilibrium. Sooner or later they reach a point where the sentiment is reversed and negative expectations become self-reinforcing in the downward direction, thereby explaining the familiar pattern of boom and bust cycles.

In Soros' view, the markets' moods — a "mood" of the markets being a prevailing bias or optimism/pessimism with which the markets look at reality — "actually can reinforce themselves so that there are these initially self-reinforcing but eventually unsustainable and self-defeating boom/bust sequences or bubbles".

A current example of reflexivity in modern financial markets is that of the debt and equity of housing markets. Lenders began to make more money available to more people in the 1990s to buy houses. More people bought houses with this larger amount of money, thus increasing the prices of these houses. Lenders looked at their balance sheets which not only showed that they had made more loans, but that their equity backing the loans—the value of the houses, had gone up (because more money was chasing the same amount of housing, relatively). Thus they lent out more money because their balance sheets looked good, and prices went up more, and they lent more. This was further amplified by public policy. Many governments see home ownership as a positive outcome and so first home owners grant and other financial subsidies — or influences to buy a home such as the exemption of a primary residence from capital gains taxation — mean that house purchases were seen as a good thing. Prices increased rapidly, and lending standards were relaxed. The salient issue regarding reflexivity is that it explains why markets gyrate over time, and do not just stick to equilibrium—they tend to overshoot or undershoot.

Bubble creation process:
-> More people bought houses with this larger amount of money
-> Increasing the prices of these houses

-> Lenders showed more loans
-> Lent out more money because their balance sheets looked good.
->
Prices went up more, and they lent more.
->
Many governments see home ownership as a positive outcome and propose financial subsidies.the exemption of a primary residence from capital gains taxation.
-> Prices increased rapidly, and lending standards were relaxed.

以下是他提出的因應策略,其共同點都是不對稱性:把自己放在有利的結果,遠大於不利結果的處境上。

一、財務上採取槓鈴策略(barbell strategy), 也就是用超積極與超保守的投資組合,取代溫和的保守、積極的投資組合。例如把八、九○%的資金,放在極保守的投資工具(像政府債),剩下的一○%到一 五%,放到極為投機的賭注上,槓桿倍數盡可能放大(像是選擇權或者期貨),這樣你的核心部位,就不會受到風險管理錯誤的影響,沒有任何黑天鵝事件可以對你 造成傷害。因為你把無法計算的風險,也就是對你有害的風險減除了,你的風險不是中度風險,而是一邊高風險,但另外一邊無風險,平均起來將是中度風險。

二、區別正面意外和負面意外。前者是指會帶來極大利益、且不可預測的事物;後者則指,因不了解而帶來嚴重傷害的事物。

三、不要尋找明確而狹隘的東西。簡單說,不要心胸狹窄、非這樣不可,而是要努力工作,讓偶發事件進入你的工作生涯;努力在準備上,而非預測上。

四、抓住任何正面機會,或任何看起來像機會的東西。機會很稀有,記住,正面黑天鵝事件的第一步:你必須暴露在其中。許多人碰到機會時,並不知道自己會得到人生中的幸運突破。努力工作,不是去做那枯燥乏味的例行性工作,而是去追逐正面機會,盡可能讓自己暴露在其中。

五、要準備好,把時間多花在自己如果判斷錯誤的衝擊。因為成功的效果是一○○%或五○%之差別根本不是太重要,但是如果一小漏洞不及早修補,可能帶給企業極大損害。

六、質疑打著「正確預測」旗幟的說法。包括政府、股市分析師、經濟學家和社會科學家。面對不確定性,人們仍會持續的預測,尤其,如果有人花錢請他們預測,此為一種制式化的欺騙;因為人們不完美的理解,因此許多假設充滿謬誤,趨勢的發展也會越來越測不準,就是索羅斯所謂的「可錯性」、「測不準原理」。要小心,當時間拉長時,準確性會迅速惡化。
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