<< Chapter < Page Chapter >> Page >

In essence, this approach was very appealing in terms of performance, development time, and cost (essentially free). Although faster and more efficient implementations are possible (e.g. C/C++ and Fortran with open-MPI , the aforementioned implementation was sufficient for our purposes).

The code utilized was initially developed for sequential execution (in SAS ) and then converted to R with similar performance. It was subsequently converted from sequential to parallel to exploit the benefits of a parallel R -implementation. The standard steps for this conversion process are pretty standard, essentially:

  1. We identify the loops which carry independent computations. we have two main loops. Firstly, simulating J portfolios can be regarded as J independent operations, which we can execute concurrently. Secondly, running the algorithm over a number of N years, can be regarded as N independent computational efforts.
  2. Vectorize loops ( Workhorse Functions).
  3. Gather results ( Combine/Gather Functions).
  4. Distribute Execution (Call functions with snow ).

Several 64 processor jobs were submitted to Rice's Cray XD1 Research Cluster (ADA) - occupying 16 nodes, each with a total of 4 processors. The jobs would take less than 20 hours to complete, for about 64 simulated tracks of 40 years each.


Preliminary results

Several simulations were run with observed, above average performance (number of portfolios inspected per simulation was in the range of J = 25 , 000 to J = 50 , 000 ). Figure 1 shows a simulation of J = 50 , 000 portfolios per year over a period of 43 years. Several interesting features can be noted through this figure. We can appreciate that any investor that made up a portfolio with an initial investment of $100,000 in 1970 and selected the same stocks chosen by our algorithm would have allowed his or her portfolio to compound to a total of $3.7M (by the end of 2008), which performed better than both an equal-investment strategy in the S&P 500 Index (about $2.7M) or a market-cap weighted investment strategy in the S&P 500 Index (slightly below $1M). Of course, we can imagine that the computational power that was used was not available in the early seventies, but moving forward it will be and to an extent this is what matters. Also it is clearly seen that the Coordinated Max-Median Rule is inherently a more volatile rule (as compared to the S&P 500). Next, Figure 2 describes 1 of 3 pilot runs that were evaluated with various measures suggesting the superiority of the max-median (as opposed to, say for instance the mean, as well as the benefit of using the “max” rather than the “min”). This seems plausible, at least heuristically, as the median is most robust (the mean is least robust), and in some sense the previous years “best” performing companies are more likely to perform better next year than the previous years “worst” performing companies (in terms of returns).

Coordinated Max-Median Rule (Single Run) 50,000 Portfolios Evaluated per Year
Coordinated Max-Median Rule (Single Run) 25,000 Portfolios Evaluated per Year with additional evaluations

Questions & Answers

can someone help me with some logarithmic and exponential equations.
Jeffrey Reply
sure. what is your question?
okay, so you have 6 raised to the power of 2. what is that part of your answer
I don't understand what the A with approx sign and the boxed x mean
it think it's written 20/(X-6)^2 so it's 20 divided by X-6 squared
I'm not sure why it wrote it the other way
I got X =-6
ok. so take the square root of both sides, now you have plus or minus the square root of 20= x-6
oops. ignore that.
so you not have an equal sign anywhere in the original equation?
Commplementary angles
Idrissa Reply
im all ears I need to learn
right! what he said ⤴⤴⤴
what is a good calculator for all algebra; would a Casio fx 260 work with all algebra equations? please name the cheapest, thanks.
Kevin Reply
a perfect square v²+2v+_
Dearan Reply
kkk nice
Abdirahman Reply
algebra 2 Inequalities:If equation 2 = 0 it is an open set?
Kim Reply
or infinite solutions?
The answer is neither. The function, 2 = 0 cannot exist. Hence, the function is undefined.
Embra Reply
if |A| not equal to 0 and order of A is n prove that adj (adj A = |A|
Nancy Reply
rolling four fair dice and getting an even number an all four dice
ramon Reply
Kristine 2*2*2=8
Bridget Reply
Differences Between Laspeyres and Paasche Indices
Emedobi Reply
No. 7x -4y is simplified from 4x + (3y + 3x) -7y
Mary Reply
is it 3×y ?
Joan Reply
J, combine like terms 7x-4y
Bridget Reply
im not good at math so would this help me
Rachael Reply
I'm not good at math so would you help me
what is the problem that i will help you to self with?
how do you translate this in Algebraic Expressions
linda Reply
Need to simplify the expresin. 3/7 (x+y)-1/7 (x-1)=
Crystal Reply
. After 3 months on a diet, Lisa had lost 12% of her original weight. She lost 21 pounds. What was Lisa's original weight?
Chris Reply
what's the easiest and fastest way to the synthesize AgNP?
Damian Reply
types of nano material
abeetha Reply
I start with an easy one. carbon nanotubes woven into a long filament like a string
many many of nanotubes
what is the k.e before it land
what is the function of carbon nanotubes?
what is nanomaterials​ and their applications of sensors.
Ramkumar Reply
what is nano technology
Sravani Reply
what is system testing?
preparation of nanomaterial
Victor Reply
Yes, Nanotechnology has a very fast field of applications and their is always something new to do with it...
Himanshu Reply
good afternoon madam
what is system testing
what is the application of nanotechnology?
In this morden time nanotechnology used in many field . 1-Electronics-manufacturad IC ,RAM,MRAM,solar panel etc 2-Helth and Medical-Nanomedicine,Drug Dilivery for cancer treatment etc 3- Atomobile -MEMS, Coating on car etc. and may other field for details you can check at Google
anybody can imagine what will be happen after 100 years from now in nano tech world
after 100 year this will be not nanotechnology maybe this technology name will be change . maybe aftet 100 year . we work on electron lable practically about its properties and behaviour by the different instruments
name doesn't matter , whatever it will be change... I'm taking about effect on circumstances of the microscopic world
how hard could it be to apply nanotechnology against viral infections such HIV or Ebola?
silver nanoparticles could handle the job?
not now but maybe in future only AgNP maybe any other nanomaterials
can nanotechnology change the direction of the face of the world
Prasenjit Reply
At high concentrations (>0.01 M), the relation between absorptivity coefficient and absorbance is no longer linear. This is due to the electrostatic interactions between the quantum dots in close proximity. If the concentration of the solution is high, another effect that is seen is the scattering of light from the large number of quantum dots. This assumption only works at low concentrations of the analyte. Presence of stray light.
Ali Reply
the Beer law works very well for dilute solutions but fails for very high concentrations. why?
bamidele Reply
how did you get the value of 2000N.What calculations are needed to arrive at it
Smarajit Reply
Privacy Information Security Software Version 1.1a
Got questions? Join the online conversation and get instant answers!
QuizOver.com Reply

Get the best Algebra and trigonometry course in your pocket!

Source:  OpenStax, The art of the pfug. OpenStax CNX. Jun 05, 2013 Download for free at http://cnx.org/content/col10523/1.34
Google Play and the Google Play logo are trademarks of Google Inc.

Notification Switch

Would you like to follow the 'The art of the pfug' conversation and receive update notifications?