Every decision is a trade. Learn to think about the ones you should do — and the ones you shouldn’t.
Trading books generally break down into two categories: the ones which claim to teach you how to make money trading, and the memoir-style books recounting scandals and bad behavior. But the former don't have profitable trades to teach; if they did they'd keep those trades to themselves. And the latter are frequently entertaining, but they don't leave you with much you can apply in your own life. The Laws of Trading is different.
All of our relationships and decisions involve trading at some level. This is a book about decision-making through the lens of a professional prop trader. For years, behavioral and cognitive scientists have shown us how human decision-making is flawed and biased. But how do you learn to avoid these problems in day-to-day decisions where you have to react in real-time? What are the important things to think about and to act on? The world needs a book by a prop trader who has lived, breathed and taught trading for a living, drawing upon years of insights on the trading floor in real markets, good and bad, whether going sideways, crashing, or bubbling over. If you can master the decision-making skills needed to profitably trade in modern markets, you can master decision-making in all walks of life. This book will teach you exactly those skills.
Introduces, develops, and applies one law per chapter, making it easy not only to remember useful concepts, but also to have them at the ready in any situation.
Shows you how to find and think about the “special edge” of your organization, and yourself.
Teaches you how to handle the interaction of people with artificially intelligent (AI) machines that make decisions, a skill that is rapidly becoming essential in the AI-driven economy of the future.
Includes a "bonus" digital ancillary, an Excel spreadsheet with various worked examples that expand on the scenarios described in the book.
Do you need to make rational decisions in a competitive environment? Almost everyone does. This book will teach you the tools that let you do your job better.

With a foreword by Clifford Asness, this book is a one stop guide to measuring the expected returns of a range of investments to enable long term investors to better manage and balance their portfolio.
For any investor, understanding the expected rewards that markets offer is central to long–term investment success. The traditional paradigm for assessing expected returns has focussed on historical performance and asset class management. However, Antti Ilmanen contends that this approach to investment decision–making is too narrow in its asset class focus and in the inputs used for assessing expected returns. He challenges investors to broaden their perspectives in two ways:
Excess returns should be harvested from diverse sources. Strategy styles and risk factors, as well as asset classes, are sources of return, thus warranting three–dimensional analysis of investments.
Any investment′s return prospects should be judged in a way that incorporates all knowledge, including historical experience, financial and behavioral theories, and current market conditions, without being overly dependent on any one of these.
Beginning with comprehensive introduction and overview, Expected Returns goes on to analyze the historical record, give a roadmap of terminology, explore rational and behavioral theories, and look at alternative interpretations for return predictability. A series of case studies provide detailed analysis of assets (equity, bond and credit risk premia, as well as alternative asset classes), dynamic strategy styles (value, carry, momentum, volatility) and underlying risk factors (growth, inflation, liquidity and tail risks), before moving back to broader themes, including time–varying expected returns, and seasonal, cyclical and secular return patterns.
Concluding with a series of investment lessons, Expected Returns is the complete guide for the long–term investor, providing wide–ranging empirical evidence, and a platform for forecasting the expected returns of an investment portfolio for asset allocation and portfolio balancing purposes.
From the Inside Flap
Expected Returns is a one–stop reference that gives investors a comprehensive toolkit for harvesting market rewards from a wide range of investments. Written by an experienced portfolio manager, scholar, strategist, investment advisor and hedge fund trader, this book challenges investors to broaden their minds from a too–narrow asset class perspective and excessive focus on historical performance. Coverage includes major asset classes (stocks, bonds, alternatives), investment strategies (value, carry, momentum, volatility) and the effects of underlying risk factors (growth, inflation, illiquidity, tail risks). Judging expected returns requires balancing historical returns with both theoretical considerations and current market conditions. Expected Returns summarizes the state of knowledge on all of these topics, providing extensive empirical evidence, surveys of risk–based and behavioral theories, and practical insights.
"This is the best book on active management ever written – and it achieves that status without mentioning a single stock or bond by name. Anyone who performs the rigorous analysis Ilmanen describes – admittedly a neat trick, since the world′s most sophisticated investors struggle to do it successfully – will beat the market."
Laurence B. Siegel, Former Director of Research, The Ford Foundation
"Antti Ilmanen shows the way forward for the investment management profession in this remarkable book. In a comprehensive and impressive way, he combines financial theory, historical performance data and forward–looking indicators, into a consistent framework for assessing expected returns and risk. His approach is both scientific and practical, based on decades of studies and his own trading experience. With a touch of personal wisdom and humility, Ilmanen′s book is a fascinating and educational journey into the future of investment management."
Knut N. Kjaer, Founding CEO of the Norwegian Government Pension Fund/NBIM and former president of RiskMetrics Group
"Ilmanen′s wonderful book manages to be exquisitely readable while covering just about every aspect of the investment process. Filled with many, many fresh and useful insights. This volume deserves to be read and then kept close at hand – because it is sure to be needed again and again."
Martin L. Leibowitz, Managing Director, Morgan Stanley, and former CIO, TIAA–CREF
"Job one for any investor is to estimate asset class returns. For the first time, Antti Ilmanen has assembled into one volume all of the tools necessary for this task: for the working money manager, a unique treasure trove of analytical techniques and empirical evidence; for the academic, a comprehensive guide to the relevant academic literature; and for the consultant, a blinding light with which to illuminate performance. Expected Returns is destined to occupy the front shelves of investment professionals around the world."
William J. Bernstein, author of The Intelligent Asset Allocator, The Birth of Plenty, and A Splendid Exchange, and co–principal of Efficient Frontier Advisors
"Antti′s synthesis of experience and theory has given us a book which fills a major gap in the literature on investing. Amazing, but true, this is the first book dedicated to the critical and challenging task of estimating how much we should expect to earn on our investments. This illuminating book, teaming with valuable insights that have never before been gathered under one roof, cannot fail to make the reader a more successful and discerning investor."
Victor Haghani, Associate Lecturer, London School of Economics, and former founding partner of LTCM
"Ilmanen has written a thorough and detailed analysis of one of the central issues in investing."
Ken French, Heidt Professor of Finance, Dartmouth College
"Investors′ decisions should be evidence based. Antti Ilmanen assembles a global body of evidence, and interprets it with insight. Read this book and you will improve your understanding of the future."
Elroy Dimson, Emeritus Professor of Finance, London Business School
"If I could choose only one book on active management, I would choose Expected Returns. This book is extremely thorough and well researched, yet direct and to the point."
Roger G. Ibbotson, Professor in the Practice of Finance, Yale School of Management, and Chairman and CIO of Zebra Capital Management

The book investigates the misapplication of conventional statistical techniques to fat tailed distributions and looks for remedies, when possible.
Switching from thin tailed to fat tailed distributions requires more than “changing the color of the dress.” Traditional asymptotics deal mainly with either n=1 or n=∞, and the real world is in between, under the “laws of the medium numbers”–which vary widely across specific distributions. Both the law of large numbers and the generalized central limit mechanisms operate in highly idiosyncratic ways outside the standard Gaussian or Levy-Stable basins of convergence.
A few examples:
- The sample mean is rarely in line with the population mean, with effect on “naïve empiricism,” but can be sometimes be estimated via parametric methods.
- The “empirical distribution” is rarely empirical.
- Parameter uncertainty has compounding effects on statistical metrics.
- Dimension reduction (principal components) fails.
- Inequality estimators (Gini or quantile contributions) are not additive and produce wrong results.
- Many “biases” found in psychology become entirely rational under more sophisticated probability distributions.
- Most of the failures of financial economics, econometrics, and behavioral economics can be attributed to using the wrong distributions.
This book, the first volume of the Technical Incerto, weaves a narrative around published journal articles.

Picking up where Liar's Poker left off (literally, in the bond dealer's desks of Salomon Brothers) the story of Long-Term Capital Management is of a group of elite investors who believed they could beat the market and, like alchemists, create limitless wealth for themselves and their partners. Founded by John Meriweather, a notoriously confident bond dealer, along with two Nobel prize winners and a floor of Wall Street's brightest and best, Long-Term Captial Management was from the beginning hailed as a new gold standard in investing. It was to be the hedge fund to end all other hedge funds: a discreet private investment club limited to those rich enough to pony up millions. It became the banks' own favourite fund and from its inception achieved a run of dizzyingly spectacular returns. New investors barged each other aside to get their investment money into LTCM's hands. But as competitors began to mimic Meriweather's fund, he altered strategy to maintain the fund's performance, leveraging capital with credit on a scale not fully understood and never seen before. When the markets in Indonesia, South America and Russia crashed in 1998 LCTM's investments crashed with them and mountainous debts accumulated. The fund was in melt-down, and threatening to bring down into its trillion-dollar black hole a host of financial instiutions from New York to Switzerland. It's a tale of vivid characters, overwheening ambition, and perilous drama told, in Roger Lowenstein's hands, with brilliant style and panache.

Machine learning (ML) is changing virtually every aspect of our lives. Today ML algorithms accomplish tasks that until recently only expert humans could perform. As it relates to finance, this is the most exciting time to adopt a disruptive technology that will transform how everyone invests for generations. Readers will learn how to structure Big data in a way that is amenable to ML algorithms; how to conduct research with ML algorithms on that data; how to use supercomputing methods; how to backtest your discoveries while avoiding false positives. The book addresses real-life problems faced by practitioners on a daily basis, and explains scientifically sound solutions using math, supported by code and examples. Readers become active users who can test the proposed solutions in their particular setting. Written by a recognized expert and portfolio manager, this book will equip investment professionals with the groundbreaking tools needed to succeed in modern finance.