Wed, Oct 1, 2014
A A A
Welcome Guest
Free Trial RSS
Get FREE trial access to our award winning publications
New Managers March 2013

Peter Urbani' Statistics - Monte Carlo may overestimate individual asset risks by up to two thirds

 

Injudicious use of Monte Carlo simulations could overestimate individual asset risks by two thirds if strict normality is assumed and the shape of the underlying distributions is ignored. Similarly total returns and Sharpe Ratios could be overstated by 20% or more when assuming strict normality. Individual assets that have positively skewed distributions may have their returns under estimated by 13% or more.

Most investors and software do not consider the asymmetry of returns and risks when conducting Monte Carlo simulations of future portfolio returns and simply rely on the central limit theorem to assume normality. Whilst the CLT certainly holds, it does so only over the long-term. In the short run, things may be very different indeed.

This month we look at the three main methods of generating correlated random deviates for the purposes of performing Monte Carlo simulations, namely;

  • The Cholesky Method,
  • The Spectral ( SVD ) Method and,
  • The Inverse method

As you may know, Monte Carlo simulations were invented by Stanislaw Ulam and John von Neumann during their work on the Manhattan project. The requirement for significant computing power meant that the method remained the preserve of think tanks, large universities and corporations until around the the 1980s and the advent of the Personal Computer. Since then, the use of the method has exploded and it has become ubiquitous in finance and financial planning even to the detriment of stopping people from trying to find closed form solutions for some problems which may have them.

Thanks to Moore’s law, most of us now have sufficient computing pow......................

To view our full article please login

This article was published in Opalesque's New Managers a top-down monthly analysis, news and research publication on the global emerging manager space.
New Managers
New Managers
New Managers

Banner

Today's Exclusives Today's Other Voices More Exclusives
Previous Opalesque Exclusives                                  
More Other Voices
Previous Other Voices                                               
Access Alternative Market Briefing


  • Top Forwarded
  • Top Tracked
  • Top Searched
  1. Legal - Court throws out lawsuits related to Fannie Mae, Freddie Mac profits, Insider case by SEC is a step removed from Herbalife itself, SEC grants Citigroup waivers, easing hedge-fund curbs[more]

    Court throws out lawsuits related to Fannie Mae, Freddie Mac profits From WSJ.com: A group of Wall Street investors on Tuesday suffered a blow in their attempts to sue the federal government over their treatment of the shareholders of mortgage finance giants Fannie Mae and Freddie Mac af

  2. Launches - Goldman Sachs Asset Management launches GS Long Short Fund, Western & Southern launching international hedge fund, Lansdowne Partners plans energy hedge fund, RBC Global Asset Management launches new RBC Funds (Lux) - Asia Ex-Japan Fund, PVE Capital latest credit strategy to launch on the Sciens managed account platform[more]

    Goldman Sachs Asset Management launches GS Long Short Fund From Marketwatch.com: Goldman Sachs Asset Management has announced the launch of the Goldman Sachs Long Short Fund, which pursues high conviction investment ideas in global equity markets through a fundamental, bottom-up approach

  3. CalPERS’ move might alter hedge fund fees for good[more]

    Benedicte Gravrand, Opalesque Geneva: When CalPERS, the California Public Employees’ Retirement System, announced on September 15th that it was unwinding its hedge-fund portfolio, it was seen by many as is a significant blow to the sector’s appeal. The Fund is

  4. Opalesque Exclusive: Institutions eye private credit over traditional fixed income[more]

    Bailey McCann, Opalesque New York: Investing in private insurance, realty tax receivables, or investment-grade short-term accounts receivable may not spring to mind as a means of mitigating risk in a portfolio, but one firm, New York-based BroadRiver Asset Management is out to change all that. Th

  5. Short-term trading quant fund beats S&P since '09[more]

    Benedicte Gravrand, Opalesque Geneva for New Managers: A relatively new multi-strategy, market-neutral quantitative hedge fund has managed to outperform the S&P500 and the HFRX Global since 2009. New Jersey-ba