Mathematicians Against Fraudulent Financial and Investment Advice (MAFFIA)
This site was created out of growing concern with the usage of less-than-fully rigorous mathematical and statistical methodologies in the financial/investment world. One example is the increasing prevalence of backtest overfitting, due in part to the ease of generating large numbers of model variations (more than statistically justified) using modern computer technology. Indeed, such statistical errors are likely the primary reason that investment strategies which look good on paper often fall flat in practice.
We are also concerned with the proliferation of quasi-mathematical investment advice and financial columns in the past few years, which appear to be based on sophisticated mathematics and statistics, but which, upon more rigorous analysis, are at best questionable. We encourage the reader to search the Internet for terms such as "stochastic oscillators," "Fibonacci ratios," "cycles," "Elliot wave," "Golden ratio," "parabolic SAR," "pivot point," "momentum," and others in the context of finance. Although such terms clearly evoke precise mathematical concepts, in fact, in almost all cases, their usage is at best scientifically unsound.
Historically scientists have led the way in exposing those who utilize pseudoscience to extract a commercial benefit. Even in the 18th century, physicists exposed the nonsense of astrologers. Yet mathematicians in the 21st century have remained disappointingly silent with the regards to those in the investment community who, knowingly or not, misuse mathematical techniques such as probability theory, statistics and stochastic calculus. Our silence is consent, making us accomplices in these abuses.
This blog and website were established with these concerns in mind. Nonetheless, our approach here is not one of confrontation, but instead one of research to better understand and mitigate these difficulties, education to assist other professionals in the field, together with unbiased testing and analysis. If you identify with our concerns, let us know and spread the word. Together we can make a difference. Contact us at
Consider also joining our MAFFIA-News email list, to receive notices of articles, blogs and other items of interest to the financial mathematica arena (low frequency -- just one post every week or two). Just send us your Google-registered email address. To register a non-Gmail address with Google, go to the Google account page, then click on "I prefer to use my current email address."
This website is operated by
- David H. Bailey, Lawrence Berkeley National Laboratory (retired), and Research Associate, University of California, Davis, Department of Computer Science.
- Marcos Lopez de Prado, Senior Managing Director, Guggenheim Partners, New York City; also Research Affiliate, Lawrence Berkeley National Laboratory.
- Qiji Jim Zhu, Professor of Mathematics, Western Michigan University.
Please send any comments or questions for this site to:
Acknowledgement of support
Lopez de Prado's research is sponsored by Guggenheim Partners, LLC. Zhu's research is sponsored by Western Michigan University.
Online demonstration tools
We operate two online tools to demonstrate the effects of backtest overfitting:
The "Mathematical Investor" blog is now online. It contains essays, philosophical musings, and news in the realm of financial mathematics, computing and scientific research.
Disclaimer and copyright
Material on this site, including papers linked to in the papers directory, articles on the blog, and software available on this site, are provided for research purposes only and do not necessarily reflect the views or policies of the respective institutions or funding agencies of the site editors. No material on this site should be interpreted as a directive to buy or sell any particular securities or to adopt any particular investment strategy, or as a forecast of future market prices or trends. Software available on this site is provided "as-is" and without any express or implied warranties, including, without limitation, the implied warranties of merchantability and fitness for a particular purpose. All material available on this site is copyrighted (c) 2016. All rights reserved.
For full details, PLEASE READ this disclaimer and copyright notice.
Here are some papers on the general topic of financial mathematics, authored by the editors of this site and by others, that are deemed of interest to readers of this community:
Here are some press reports mentioning one or more of us, particularly in the realm of mathematics in general or financial mathematics in particular: