Ponzi Scheme, Pyramid Scheme and Economic Bubble

Unraveling of a Ponzi scheme

When a Ponzi scheme is not stopped by the authorities, it sooner or later falls apart for one of the following reasons:[1]

  1. The promoter vanishes, taking all the remaining investment money (minus payouts to investors already made).
  2. Since the scheme requires a continual stream of investments to fund higher returns, once investment slows down, the scheme collapses as the promoter starts having problems paying the promised returns (the higher the returns, the greater the risk of the Ponzi scheme collapsing). Such liquidity crises often trigger panics, as more people start asking for their money, similar to a bank run.
  3. External market forces, such as a sharp decline in the economy (for example, the Madoff investment scandal during the market downturn of 2008), cause many investors to withdraw part or all of their funds.

Similar schemes

  • A pyramid scheme is a form of fraud similar in some ways to a Ponzi scheme, relying as it does on a mistaken belief in a nonexistent financial reality, including the hope of an extremely high rate of return. However, several characteristics distinguish these schemes from Ponzi schemes:[1]
    • In a Ponzi scheme, the schemer acts as a “hub” for the victims, interacting with all of them directly. In a pyramid scheme, those who recruit additional participants benefit directly. (In fact, failure to recruit typically means no investment return.)
    • A Ponzi scheme claims to rely on some esoteric investment approach and often attracts well-to-do investors; whereas pyramid schemes explicitly claim that new money will be the source of payout for the initial investments.
    • A pyramid scheme typically collapses much faster because it requires exponential increases in participants to sustain it. By contrast, Ponzi schemes can survive simply by persuading most existing participants to reinvest their money, with a relatively small number of new participants.
  • An economic bubble: A bubble is similar to a Ponzi scheme in that one participant gets paid by contributions from a subsequent participant (until inevitable collapse). A bubble involves ever-rising prices in an open market (for example stock, housing, or tulip bulbs) where prices rise because buyers bid more because prices are rising. Bubbles are often said to be based on the “greater fool” theory. As with the Ponzi scheme, the price exceeds the intrinsic value of the item, but unlike the Ponzi scheme, there is no single person misrepresenting the intrinsic value.


Madoff investment scandal


Ponzi scheme

A Ponzi scheme is a fraudulent investment operation where the operator, an individual or organization, pays returns to its investors from new capital paid to the operators by new investors, rather than from profit earned by the operator. Operators of Ponzi schemes usually entice new investors by offering higher returns than other investments, in the form of short-term returns that are either abnormally high or unusually consistent. The perpetuation of the high returns requires an ever-increasing flow of money from new investors to sustain the scheme.[1]

Greater fool theory

The greater fool theory states that the price of an object is determined not by its intrinsic value, but rather by irrational beliefs and expectations of market participants.

In real estate, the greater fool theory can drive investment under the expectation that prices always rise.[5][6] A period of rising prices may cause lenders to underestimate the risk of default.[7]

In the stock market, the greater fool theory is also called survivor investing, is defined by Investopedia as the belief held by someone who makes a questionable investment, with the assumption that they will be able to sell it later to “a greater fool”; in other words, buying something not because you believe that it is worth the price, but rather because you believe that you will be able to sell it to someone else at an even higher price.


Keynesian beauty contest

Keynes described the action of rational agents in a market using an analogy based on a fictional newspaper contest, in which entrants are asked to choose the six prettiest faces from a hundred photographs. Those who picked the most popular faces are then eligible for a prize.

A naive strategy would be to choose the face that, in the opinion of the entrant, is the most beautiful. A more sophisticated contest entrant, wishing to maximize the chances of winning a prize, would think about what the majority perception of beauty is, and then make a selection based on some inference from his knowledge of public perceptions. This can be carried one step further to take into account the fact that other entrants would each have their own opinion of what public perceptions are. Thus the strategy can be extended to the next order and the next and so on, at each level attempting to predict the eventual outcome of the process based on the reasoning of other rational agents.

“It is not a case of choosing those [faces] that, to the best of one’s judgment, are really the prettiest, nor even those that average opinion genuinely thinks the prettiest. We have reached the third degree where we devote our intelligences to anticipating what average opinion expects the average opinion to be. And there are some, I believe, who practice the fourth, fifth and higher degrees.” (Keynes, General Theory of Employment Interest and Money, 1936).



2002 Breeders’ Cup betting scandal

Greg Young – CQRS and Event Sourcing – Code on the Beach 2014