English
Related papers

Related papers: Crashes as Critical Points

200 papers

We propose that the minimal requirements for a model of stock market price fluctuations should comprise time asymmetry, robustness with respect to connectivity between agents, ``bounded rationality'' and a probabilistic description. We also…

Condensed Matter · Physics 2007-05-23 Anders Johansen , Didier Sornette

The price-bubble and crash process formation is theoretically investigated in a two-asset equilibrium model. Sufficient and necessary conditions are derived for the existence of average equilibrium price dynamics of different agent-based…

Trading and Market Microstructure · Quantitative Finance 2024-09-06 Francesco Cordoni

The existence of the pricing kernel is shown to imply the existence of an ambient information process that generates market filtration. This information process consists of a signal component concerning the value of the random variable X…

General Finance · Quantitative Finance 2011-03-17 Grzegorz Andruszkiewicz , Dorje C. Brody

Imitative and contrarian behaviors are the two typical opposite attitudes of investors in stock markets. We introduce a simple model to investigate their interplay in a stock market where agents can take only two states, bullish or bearish.…

Statistical Mechanics · Physics 2008-12-02 A. Corcos , J. -P. Eckmann , A. Malaspinas , Y. Malevergne , D. Sornette

The drift burst hypothesis postulates the existence of short-lived locally explosive trends in the price paths of financial assets. The recent U.S. equity and treasury flash crashes can be viewed as two high-profile manifestations of such…

Econometrics · Economics 2026-01-16 Kim Christensen , Roel C. A. Oomen , Roberto Renò

We critically review recent claims that financial crashes can be predicted using the idea of log-periodic oscillations or by other methods inspired by the physics of critical phenomena. In particular, the October 1997 `correction' does not…

Statistical Mechanics · Physics 2009-10-31 Laurent Laloux , Marc Potters , Rama Cont , Jean-Pierre Aguilar , Jean-Philippe Bouchaud

Catastrophes of all kinds can be roughly defined as short duration-large amplitude events following and followed by long periods of "ripening". Major earthquakes surely belong to the class of 'catastrophic' events. Because of the space-time…

Data Analysis, Statistics and Probability · Physics 2015-06-04 Randall D. Peters , Martine Le Berre , Yves Pomeau

By combining (i) the economic theory of rational expectation bubbles, (ii) behavioral finance on imitation and herding of investors and traders and (iii) the mathematical and statistical physics of bifurcations and phase transitions, the…

Statistical Finance · Quantitative Finance 2010-07-08 Zhi-Qiang Jiang , Wei-Xing Zhou , Didier Sornette , Ryan Woodard , Ken Bastiaensen , Peter Cauwels

We present a self-consistent model for explosive financial bubbles, which combines a mean-reverting volatility process and a stochastic conditional return which reflects nonlinear positive feedbacks and continuous updates of the investors'…

Risk Management · Quantitative Finance 2014-08-26 L. Lin , Ren R. E , D. Sornette

We study and generalize in various ways the model of rational expectation (RE) bubbles introduced by Blanchard and Watson in the economic literature. First, bubbles are argued to be the equivalent of Goldstone modes of the fundamental…

Statistical Mechanics · Physics 2009-11-07 D. Sornette , Y. Malevergne

We present an analysis of the time behavior of the $S\&P500$ (Standard and Poors) New York stock exchange index before and after the October 1987 market crash and identify precursory patterns as well as aftershock signatures and…

Condensed Matter · Physics 2009-10-28 Didier Sornette , Anders Johansen , Jean-Philippe Bouchaud

We develop a strong diagnostic for bubbles and crashes in bitcoin, by analyzing the coincidence (and its absence) of fundamental and technical indicators. Using a generalized Metcalfe's law based on network properties, a fundamental value…

Econometrics · Economics 2018-03-16 Spencer Wheatley , Didier Sornette , Tobias Huber , Max Reppen , Robert N. Gantner

This paper develops a two-step estimation methodology, which allows us to apply catastrophe theory to stock market returns with time-varying volatility and model stock market crashes. Utilizing high frequency data, we estimate the daily…

Statistical Finance · Quantitative Finance 2013-05-23 Jozef Barunik , Jiri Kukacka

We define a financial bubble as a period of unsustainable growth, when the price of an asset increases ever more quickly, in a series of accelerating phases of corrections and rebounds. More technically, during a bubble phase, the price…

Risk Management · Quantitative Finance 2014-04-09 Didier Sornette , Peter Cauwels

Critical transitions in multistable systems have been discussed as models for a variety of phenomena ranging from the extinctions of species to socio-economic changes and climate transitions between ice-ages and warm-ages. From bifurcation…

Data Analysis, Statistics and Probability · Physics 2018-12-24 Xiaozhu Zhang , Christian Kuehn , Sarah Hallerberg

We propose a straightforward extension of our previously proposed log-periodic power law model of the ``anti-bubble'' regime of the USA market since the summer of 2000, in terms of the renormalization group framework to model critical…

Physics and Society · Physics 2008-12-02 W. -X. Zhou , D. Sornette

We present a synthesis of all the available empirical evidence in the light of recent theoretical developments for the existence of characteristic log-periodic signatures of growing bubbles in a variety of markets including 8 unrelated…

Condensed Matter · Physics 2007-05-23 Anders Johansen , Didier Sornette , Olivier Ledoit

In social networks, bursts of activity often result from the imitative behavior between interacting agents. The Ising model, along with its variants in the social sciences, serves as a foundational framework to explain these phenomena…

Adaptation and Self-Organizing Systems · Physics 2023-08-29 Sornette Didier , Sandro Lera , Jianhong Lin , Ke Wu

This work presents an asset pricing model that under rational expectation equilibrium perspective shows how, depending on risk aversion and noise volatility, a risky-asset has one equilibrium price that differs in term of efficiency: an…

General Finance · Quantitative Finance 2014-09-18 Matteo Formenti

The critical brain hypothesis receives increasing support from recent experimental results. It postulates that the brain is at a critical point between an ordered and a chaotic regime, sometimes referred to as the "edge of chaos." Another…

Disordered Systems and Neural Networks · Physics 2022-02-08 Lorenz Baumgarten , Stefan Bornholdt