Tuesday, March 29, 2011

Beautiful People Generally Happier, UT Researchers Find

They say money can't buy happiness — but can good looks do the job?

via www.texasexes.org

Although this is interesting, it's sure to annoy econometricians.

IDC Forecasts Windows SmartPhone to be number #2 by 2015

IDC - Press Release - prUS22762811

I thought I should store this so I can make fun of IDC four years from now.

Saturday, March 26, 2011

The subfiles LaTeX package

If your lifetime plan includes writing an article or a book, you may need to learn how write a rather large document in LaTeX. Or maybe you are co-writing a document (Andrew and I did a big homework once and synchronizing files can be tricky).

One important thing is to use a file synchronizer like Windows Live Sync or Dropbox, but the other is to teach LaTeX to use multiple files.

The subfiles package can help with that. The documentation for subfiles is here.

It allows you to write a master file and several subfiles that can be compiled independently, so you can work on and compile each subfile (for example, a chapter or a section) and see the results, and compile the master file to see the full book. A simple and useful example can be found in Wikibooks.

Wednesday, March 23, 2011

Libya rebels name US-based academic as finance chief | News by Country | Reuters

The relations between First Quantum and the Democratic Republic of Congo have gone from bad to worse in recent months, after the country expropriated the miner’s $765 million Kolwezi copper tailings project in September.   Blog 

via af.reuters.com

I was going to be his TA this quarter. Well, if he wants me, I'll still be!

Thursday, March 17, 2011

U.S. Reacts to Nuclear Danger: Panic for Potassium Iodide - TIME

The good news in Japan was that the winds had been pushing the radiated plumes from the stricken Fukushima Daiichi nuclear power plant out into the Pacific Ocean, away from populated areas. The winds would likely prevent more harm from happening to the earthquake-and-tsunami-battered region.

via www.time.com

The law of demand in action: a bottle of iodide pill went from $6 to $140 in the West Coast.

Wednesday, March 16, 2011

Tutorial: Portfolio Optimization Using R

I wrote a tutorial on how to implement some portfolio optimizers in R for a class. The tutorial implements three types of factor models:

  • A Fama-French three factor model

  • An industry cross-sectional model

  • A principal component analysis model

This is for instructional purposes only: it's not a software for you to plug in your portfolio and start investing. However, if you make millions doing so, I wouldn't mind a 10% cut.

Two things that are not in the tutorial but that are important if you really want to implement something for real use are:

  • Selecting the data that will be used for optimization (I use the Dow Jones Industrial Average from 2006 to 2010)

  • Optimizing Sharpe ratios by combining the portfolio with a risk-free asset (such as T-bills)

Download Factor Models

Monday, March 14, 2011

The Durbin Amendment

I recently had to prepare a paper about the impacts of the Dodd-Frank legislation for a class. Rather randomly, I chose the Durbin Amendment, a provision that increases regulation on the debit card market. What I learned about the debit and credit card market was fascinating.

The amendment passed into law in July 2010 and the Fed is now discussing how it will be regulated, and this is where the relevant points appear. For example, the amendment requires a price cap on the fees that merchants have to pay, but it doesn't say how much. The average fee in 2010 was about 44 cents, and the Fed set the cap at 12 cents, cutting heavily into the profits of (I can safely say)  your bank. As a consequence, you may pay more for checking, but is this really bad?

Download Durbin Amendment

Thursday, March 10, 2011

Managerial economics (B ECON 300) class notes

It is very possible that many of my Managerial Economics students will scour the web for class notes (instead of using the course website). And maybe, just maybe, after spending some time on Wikipedia's article on Managerial Economics and in some random essay mills, they may find the lecture notes here.

It's very possible that looking at the course website would have been faster, but the course website is not integrated with Facebook and not accessible through Google, so I'm just making it easy on them.

Download Managerial Economics Lecture Notes

Wednesday, March 09, 2011

Tuesday, March 08, 2011

xkcd: Advertising

via xkcd.com

Nothing more annoying for a mathematician (of sorts) than the "up to 15% or more"...

The joy of copulas: An R tutorial

I explore copulas by creating a model with four funds that track market indexes
for stocks, bonds, dollar and commodities. I then use the model to generate simulated values
and test the performance of a model portfolio using the real returns and the simulated returns
to calculate the value at risk (VaR) and the expected shortfall (ES).

Download Copulas