The aim of this paper is to present novel tests for the early causal diagnostic of positive and negative bubbles in the S&P 500 index and the detection of End-of-Bubble signals with their corresponding confidence levels. We use monthly S&P 500 data covering the period from August 1791 to August...

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...

This paper examines real-time applications of quickest disorder detection techniques for timing stock markets. The focus is on the stochastic disorder model by Shiryaev, Zhitlukhin, and Ziemba (2014, 2015), Zhitlukhin and Ziemba (2016) and their optimal stopping rule. The model uses sequential...

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...

We study an economy populated by three groups of logarithmic agents: Constrained agents subject to a portfolio constraint that limits their risk-taking, unconstrained agents subject to a standard nonnegative wealth constraint, and arbitrageurs with access to uncollateralized credit. Such credit...

Using the mechanics of creep in material sciences as a metaphor, we present a general framework to understand the evolution of financial, economic and social systems and to construct scenarios for the future. In a nutshell, highly non-linear out-of-equilibrium systems subjected to exogenous...

Identifying unambiguously the presence of a bubble in an asset price remains an unsolved problem in standard econometric and financial economic approaches. A large part of the problem is that the fundamental value of an asset is, in general, not directly observable and it is poorly constrained...