Didier Sornette – författare

The book is motivated by the disruptions introduced by the financial crisis and the many attempts that have followed to propose new ideas and remedies.

Assembling contributions by authors from a variety of backgrounds, this collection illustrates the potentials resulting from the marriage of financial economics, complexity theory and an out-of-equilibrium view of the economic world. Challenging the traditional hypotheses that lie behind financial market functioning, new evidence is provided about the hidden factors fuelling bubbles, the impact of agents’ heterogeneity, the importance of endogeneity in the information transmission mechanism, the dynamics of herding, the sources of volatility, the portfolio optimization techniques, the financial innovation and the trend identification in a nonlinear time-series framework.

Presenting the advances made in financial market analysis, and putting emphasis on nonlinear dynamics, this book suggests interdisciplinary methodologies for the study of well-known stylised facts and financial abnormalities. This book was originally published as a special issue of The European Journal of Finance.

The book is motivated by the disruptions introduced by the financial crisis and the many attempts that have followed to propose new ideas and remedies.

Assembling contributions by authors from a variety of backgrounds, this collection illustrates the potentials resulting from the marriage of financial economics, complexity theory and an out-of-equilibrium view of the economic world. Challenging the traditional hypotheses that lie behind financial market functioning, new evidence is provided about the hidden factors fuelling bubbles, the impact of agents’ heterogeneity, the importance of endogeneity in the information transmission mechanism, the dynamics of herding, the sources of volatility, the portfolio optimization techniques, the financial innovation and the trend identification in a nonlinear time-series framework.

Presenting the advances made in financial market analysis, and putting emphasis on nonlinear dynamics, this book suggests interdisciplinary methodologies for the study of well-known stylised facts and financial abnormalities. This book was originally published as a special issue of The European Journal of Finance.

The scientific study of complex systems has transformed a wide range of disciplines in recent years, enabling researchers in both the natural and social sciences to model and predict phenomena as diverse as earthquakes, global warming, demographic patterns, financial crises, and the failure of materials. In this book, Didier Sornette boldly applies his varied experience in these areas to propose a simple, powerful, and general theory of how, why, and when stock markets crash. Most attempts to explain market failures seek to pinpoint triggering mechanisms that occur hours, days, or weeks before the collapse. Sornette proposes a radically different view: the underlying cause can be sought months and even years before the abrupt, catastrophic event in the build-up of cooperative speculation, which often translates into an accelerating rise of the market price, otherwise known as a "bubble." Anchoring his sophisticated, step-by-step analysis in leading-edge physical and statistical modeling techniques, he unearths remarkable insights and some predictions--among them, that the "end of the growth era" will occur around 2050. Sornette probes major historical precedents, from the decades-long "tulip mania" in the Netherlands that wilted suddenly in 1637 to the South Sea Bubble that ended with the first huge market crash in England in 1720, to the Great Crash of October 1929 and Black Monday in 1987, to cite just a few. He concludes that most explanations other than cooperative self-organization fail to account for the subtle bubbles by which the markets lay the groundwork for catastrophe. Any investor or investment professional who seeks a genuine understanding of looming financial disasters should read this book. Physicists, geologists, biologists, economists, and others will welcome Why Stock Markets Crash as a highly original "scientific tale," as Sornette aptly puts it, of the exciting and sometimes fearsome--but no longer quite so unfathomable--world of stock markets.

This book explores the major differences between the kinds of risk encountered in different sectors of industry - production (including agriculture) and services - and identifies the main features of accidents within different industries.

Because of these differences, unique risk-mitigation measures will need to be implemented in one industry that cannot be implemented in another, leading to large managerial differences between these broad economic sectors.

This book is mainly intended for executives, strategists, senior risk managers of enterprise-wide organizations and risk management experts engaged in academic or consulting work. By setting out clearly the sector differences in risk management, the authors aim to improve the practice of general risk assessment with regard to identifying and prioritizing risks, and of risk control with regard to planning appropriate mitigation measures.

After a major disaster, when investigators are piecing together the story of what happened, a striking fact often emerges: before disaster struck, some people in the organization involved were aware of dangerous conditions that had the potential to escalate to a critical level. But for a variety of reasons, this crucial information did not reach decision-makers. So, the organization moved ever closer to catastrophe, effectively unaware of the possible threat—despite the fact that some of its employees could see it coming.

What is the problem with communication about risk in an organization, and why does this problem exist? What stops people in organizations or project teams from freely reporting and discussing critical risks? This book seeks to answer these questions, starting from a deep analysis of 20 disasters where the concealment of risks played a major part.

These case studies are drawn from around the world and span a range of industries: civil nuclear power,coal, oil and gas production, hydropower energy, metals and mining, space exploration, transport, finance, retail manufacturing and even the response of governments to wars, famines and epidemics.

Together, case studies give an insight into why people hesitate to report risks—and even when they do, why their superiors often prefer to ignore the news. 

The book reviews existing research on the challenges of voice and silence in organizations.

This helps to explain more generally why people dread passing on bad news to others—and why in the workplace they prefer to keep quiet about unpleasant facts or potential risks when they are talking to superiors and colleagues.

The discussion section of the book includes important examples of concealment within the Chinese state hierarchy as well as by leading epidemiologists and governments in the West during the novel coronavirus outbreak in Wuhan in 2019-2020. The full picture of the very early stage of the COVID-19 pandemic remains unclear, and further research is obviously needed to better understand what motivated some municipal, provincial and national officials in China as well as Western counterparts to obfuscate facts in their internal communications about many issues associated with the outbreak.

This book discusses the risks of information concealment in the context of major natural or industrial disasters – offering detailed descriptions and analyses of some 25 historical cases (Three Mile Island nuclear accident, Bhopal disaster, Challenger Space Shuttle explosion, Chernobyl nuclear disaster, Deepwater Horizon oil spill, Fukushima-Daiichi nuclear disaster, Enron’s bankruptcy, Subprime mortgage crisis, Worldwide Spanish flu and SARS outbreaks, etc.) and applying these insights to selected on-going cases where such information concealment is suspected. Some successful examples of preventive anti-concealment practice are also presented.

In the book, the term ‘concealment’ is used to represent the two distinct behaviors uncovered in the investigations: (i) facts and information about an organization and its functioning being hidden from those that need them – here the concealment can be due to various factors, such as complexity and miscommunication, to name but two – and (ii) the conscious and deliberate action of keeping important information secret or misrepresenting it. This second meaning makes up a surprisingly important part of the evidence presented. 

Accordingly, emphasis has been put on this second aspect and the approach is more pragmatic than academic, remaining focused on evidence-based practical and useful factors. It raises awareness and provides valuable lessons for decision- makers, risk specialists and responsible citizens alike. This work is also intended as a fact-based reference work for future academic and scholarly investigations on the roots of the problem, in particular regarding any psychological or sociological modeling of human fallibility.  

The history of mankind is a story of ascent to unprecedented levels of comfort, productivity and consumption, enabled by the increased mastery of the basic reserves and flows of energy. This miraculous trajectory is confronted by the consensus that anthropogenic emissions are harmful and must decrease, requiring de-carbonization of the energy system.  

The mature field of indicator-based sustainability assessment provides a rigorous systematic framework to balance the pros and cons of the various existing energy technologies using lifecycle assessments and weighting criteria covering the environment, economy, and society, as the three pillars of sustainability. In such a framework, nuclear power is ranked favorably, but since emphasis is often placed on radioactive wastes and risk aversion, renewables are usually ranked top. However, quantifying the severity of the consequences of nuclear accidents on a rough integral cost basis and balancing severity with low core-damage accident probabilities indicates that the average external cost of such accidents is similar to that of modern renewables, and far less than carbon-based energy.

This book formulates the overall goal and associated unprecedented demanding criteria of taming nuclear risks by excluding mechanisms that lead to serious accidents and avoiding extremely long stewardship times as far as possible, by design. It reviews the key design features of nuclear power generation, paving the way for the exploration of radically new combinations of technologies to come up with “revolutionary” or even “exotic” system designs.  The book also provides scores for the selected designs and discusses the high potential for far-reaching improvements, with small modular lines of the best versions as being most attractive.

Given the ambition and challenges, the authors call for an urgent increase in funding of at least two orders of magnitude for a broad international civilian “super-Apollo” program on nuclear energy systems. Experience indicates that such investments in fundamental technologies enable otherwise unattainable revolutionary innovations with massive beneficial spillovers to the private sector and the public for the next generations.

Portfolio analysis and optimization, together with the associated risk assessment and management, require knowledge of the likely distributions of returns at different time scales and insights into the nature and properties of dependences between the different assets.

This book offers an original and thorough treatment of these two domains, focusing mainly on the concepts and tools that remain valid for large and extreme price moves. Strong emphasis is placed on the theory of copulas and their empirical testing and calibration, because they offer intrinsic and complete measures of dependences.

Extreme Financial Risks will be useful to:

students looking for a general and in-depth introduction to the field;

financial engineers, economists, econometricians, actuarial professionals;

researchers and mathematicians looking for a synoptic view comparing the pros and cons of different modelling strategies; and

quantitative practitioners for the insights offered on the subtleties and the many dimensional components of both risk and dependence.

In toto, the content of this book will also be useful to a broader scientific community interested in quantifying the complexity of many natural and artificial processes in which a growing emphasis is on the role and importance of extreme phenomena.