Economic bubble


An economic bubble is a period when current asset prices greatly exceed their intrinsic valuation, being the valuation that the underlying long-term fundamentals justify. Bubbles can be caused by overly optimistic projections about the scale and sustainability of growth, and/or by the belief that intrinsic valuation is no longer relevant when making an investment. They have appeared in most asset classes, including stocks, commodities, real estate, and even esoteric assets. Bubbles usually form as a result of either excess liquidity in markets, and/or changed investor psychology. Large multi-asset bubbles, are attributed to central banking liquidity.
In the early stages of a bubble, many investors do not recognise the bubble for what it is. People notice the prices are going up and often think it is justified. Therefore bubbles are often conclusively identified only in retrospect, after the bubble has already "popped" and prices have crashed.
The bursting of a bubble is usually followed by a rapid decline in prices, which can lead to significant financial losses and broader economic disruption.

Origin of term

The term "bubble", in reference to financial crisis, originated in the 1711–1720 British South Sea Bubble, and originally referred to the companies themselves, and their inflated stock, rather than to the crisis itself. This was one of the earliest modern financial crises; other episodes were referred to as "manias", as in the Dutch tulip mania. The metaphor indicated that the prices of the stock were inflated and fragile – expanded based on nothing but air, and vulnerable to a sudden burst, as in fact occurred.
Some later commentators have extended the metaphor to emphasize the suddenness, suggesting that economic bubbles end "All at once, and nothing first, / Just as bubbles do when they burst," though theories of financial crises such as debt deflation and the Financial Instability Hypothesis suggest instead that bubbles burst progressively, with the most vulnerable assets failing first, and then the collapse spreading throughout the economy.
Over time, the term evolved from describing specific speculative companies to referring more broadly to any situation in which asset prices become detached from their fundamental value.

Types

There are different types of bubbles, with economists primarily interested in two major types of bubbles: The equity bubble and the ''debt bubble.''

Equity bubble

An equity bubble is characterised by tangible investments and the unsustainable desire to satisfy a legitimate market in high demand. These kind of bubbles are characterised by easy liquidity, tangible and real assets, and an actual innovation that boosts confidence. The injection of funds into the business cycle is capable of accelerating the innovation process and propelling faster productivity growth. Examples of an equity bubble are the Tulip Mania, the cryptocurrency bubble, the dot-com bubble, and the Roaring Twenties

Debt bubble

A debt bubble is characterised by intangible or credit based investments with little ability to satisfy growing demand in a non-existent market. These bubbles are not backed by real assets and are based on frivolous lending in the hope of returning a profit or security. These bubbles usually end in debt deflation causing bank runs or a currency crisis when the government can no longer maintain the fiat currency. Examples are the Roaring Twenties stock market bubble and the United States housing bubble.
In practice, many bubbles combine elements of both equity and debt bubbles, often starting with real investment opportunities and later being amplified by excessive credit.
Debt bubbles tend to have more severe and systemic economic consequences than equity bubbles because they directly affect the banking and financial system.

Impact

The impact of economic bubbles is debated within and between schools of economic thought; they are not generally considered beneficial, but it is debated how harmful their formation and bursting is.
Within mainstream economics, many believe that bubbles cannot be identified in advance, cannot be prevented from forming, that attempts to "prick" the bubble may cause financial crisis, and that instead authorities should wait for bubbles to burst of their own accord, dealing with the aftermath via monetary policy and fiscal policy.
Political economist Robert E. Wright argues that bubbles can be identified before the fact with high confidence.
In addition, the crash which usually follows an economic bubble can destroy a large amount of wealth and cause continuing economic malaise; this view is particularly associated with the debt-deflation theory of Irving Fisher, and elaborated within Post-Keynesian economics.
A protracted period of low risk premiums can simply prolong the downturn in asset price deflation, as was the case of the Great Depression in the 1930s for much of the world and the 1990s for Japan. Not only can the aftermath of a crash devastate the economy of a nation, but its effects can also reverberate beyond its borders.

Effect upon spending

Another important aspect of economic bubbles is their impact on spending habits. Market participants with overvalued assets tend to spend more because they "feel" richer. Many observers quote the housing market in the United Kingdom, Australia, New Zealand, Spain and parts of the United States in recent times, as an example of this effect. When the bubble inevitably bursts, those who hold on to these overvalued assets usually experience a feeling of reduced wealth and tend to cut discretionary spending at the same time, hindering economic growth or, worse, exacerbating the economic slowdown.
In an economy with a central bank, the bank may therefore attempt to keep an eye on asset price appreciation and take measures to curb high levels of speculative activity in financial assets. This is usually done by increasing the interest rate. Historically, this is not the only approach taken by central banks. It has been argued that they should stay out of it and let the bubble, if it is one, take its course.
Some economists argue that, despite their risks, bubbles can temporarily stimulate investment and innovation, leaving behind lasting economic benefits after they burst.

In economics

Investor George Soros, influenced by ideas put forward by his tutor, Karl Popper, has been an active promoter of the relevance of reflexivity to economics, first propounding it publicly in his 1987 book The alchemy of finance. He regards his insights into market behaviour from applying the principle as a major factor in the success of his financial career.
Reflexivity is inconsistent with general 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 economic fundamentals, which are unaffected by prices. Reflexivity asserts that prices do in fact influence the fundamentals and that these newly influenced sets 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. An example Soros cites is the procyclical nature of lending, that is, the willingness of banks to ease lending standards for real estate loans when prices are rising, then raising standards when real estate prices are falling, reinforcing the boom and bust cycle. He further suggests that property price inflation is essentially a reflexive phenomenon: house prices are influenced by the sums that banks are prepared to advance for their purchase, and these sums are determined by the banks' estimation of the prices that the property would command.
Soros has often claimed that his grasp of the principle of reflexivity is what has given him his "edge" and that it is the major factor contributing to his successes as a trader. For several decades there was little sign of the principle being accepted in mainstream economic circles, but there has been an increase of interest following the crash of 2008, with academic journals, economists, and investors discussing his theories.
Economist and former columnist of the Financial Times, Anatole Kaletsky, argued that Soros' concept of reflexivity is useful in understanding China's economy and how the Chinese government manages it.
Eugene Fama, the Nobel laureate in economics who has often been described as "the father of modern finance", has expressed skepticism about the notion that economic bubbles can be identified. He argues that for something to be a bubble, its ending needs to be predicted in real time, not just after the fact. He argues that conventional rhetoric about bubbles proposes no testable propositions and no ways to measure a bubble.
The concept of reflexivity is often used to explain the formation and collapse of economic bubbles.
The relevance of reflexivity to economics remains debated, with no consensus in mainstream economic theory.

Causes

It has been suggested that bubbles may be rational, intrinsic, and contagious. To date, there is no widely accepted theory to explain their occurrence. Recent computer-generated agency models suggest excessive leverage could be a key factor in causing financial bubbles.
Puzzlingly for some, bubbles occur even in highly predictable experimental markets, where uncertainty is eliminated and market participants should be able to calculate the intrinsic value of the assets simply by examining the expected stream of dividends. Nevertheless, bubbles have been observed repeatedly in experimental markets, even with participants such as business students, managers, and professional traders. Experimental bubbles have proven robust to a variety of conditions, including short-selling, margin buying, and insider trading.
While there is no clear agreement on what causes bubbles, there is evidence to suggest that they are not caused by bounded rationality or assumptions about the irrationality of others, as assumed by greater fool theory. It has also been shown that bubbles appear even when market participants are well capable of pricing assets correctly. Further, it has been shown that bubbles appear even when speculation is not possible or when over-confidence is absent.
More recent theories of asset bubble formation suggest that they are likely sociologically-driven events, thus explanations that merely involve fundamental factors or snippets of human behavior are incomplete at best. For instance, qualitative researchers Preston Teeter and Jorgen Sandberg argue that market speculation is driven by culturally-situated narratives that are deeply embedded in and supported by the prevailing institutions of the time. They cite factors such as bubbles forming during periods of innovation, easy credit, loose regulations, and internationalized investment as reasons why narratives play such an influential role in the growth of asset bubbles.