It is commonly overlooked that the concept of market efficiency embowers a time-dimension. Illustrating with an example from the class of persistent random walks, we show that a price process can be a martingale on one time-scale but inefficient on another. This means that just as market...

We examine the predictive power of market-based indicators over the positive and negative stock market bubbles via an application of the LPPLS Confidence TM Multi-scale Indicators to the S&P 500 index. We find that the LPPLS framework is able to successfully capture, ex-ante, some of the...

Puzzling deviations from the predictions of rational finance theory have been extensively documented empirically. In this paper, we offer an explanation for one of these anomalies, the “excess volatility puzzle”, i.e. the observation that prices fluctuate more than fundamentally justified....

To study coordination in complex social systems such as financial markets, the authors introduce a new prediction market set-up that accounts for fundamental uncertainty. Nonetheless, the market is designed so that its total value is known, and thus its rationality can be evaluated. In two...

To study coordination in complex social systems such as financial markets, the authors introduce a new prediction market set -up that accounts for fundamental uncertainty. Nonetheless, the market is designed so that its total value is known, and thus its rationality can be evaluated. In two...

We propose an extension of the class of rational expectations bubbles (REBs) to the more general rational beliefs setting of Kurz (1994a,b). In a potentially non-stationary but stationarizable environment, among an heterogenous population of agents, it is possible to hold more than one...

We present a dynamic Rational Expectations (RE) bubble model of prices with the intention to evaluate it on optimal investment strategies applied to Bitcoin. Our bubble model is defined as a geometric Brownian motion combined with separate crash (and rally) discrete jump distributions associated...

At odds with the common “rational expectations” framework for bubbles, economists like Hyman Minsky, Charles Kindleberger and Robert Shiller have documented that irrational behavior, ambiguous information or certain limits to arbitrage are essential drivers for bubble phenomena and financial...

In the data mining and machine learning fields, forecasting the direction of price change can be generally formulated as a supervised classfii cation. This paper attempts to predict the direction of daily changes of the Nasdaq Composite Index (NCI) and of the Standard & Poor's 500 Composite...