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I’m a HUGE fan of Structural Equation Modeling. Heck, I’ve even begun teaching short SEM workshops. (seriously, if you want, email me and we’ll talk). For those of you unfamiliar with the technique, it’s awesome for three main reasons. It’s a method of teasing apart ... [Read more...]

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In the last post I showed how to pick the parameters for the ARMA model. The next step is to determine the position at the close. One way to do that is by a one day ahead prediction, if the prediction comes negative (remember the series we are operating on ... [Read more...]

Just got back from a couple of months vacation in NZ so brief posting this month. Another common field of mean reversion analysis relates to commodities and commodity related stocks.  In this analysis, I compare the prompt month crude oil price, CL1 to the price of XOP, an ETF that ... [Read more...]

We've introduced R in the organization!It is running along with the heavy weights of statistical analysis like SAS, SPSS, Matlab. Here's what we did and how we did it...HOW DID IT START?I started learning R last year and loved its simplicity and power.... [Read more...]

While we were at R/Finance in Chicago over the weekend (more on that later), it was a great pleasure to meet in person Paul Teetor, author of the R Cookbook (published by O'Reilly). If you haven't picked it up yet, I recommend checking it out: if you already have ... [Read more...]

This was my first year to attend the R/Finance conference that focuses on the use R programming in applied finance.  I was unable to get out there until mid-morning on Friday, so I missed Jeff Ryan’s tutorial on Automated Trading … Continue reading → [Read more...]

I am not a big fan of those ceremonies, where some actors pretend that they are extremely happy to be there, and then some win a trophy, some don't, and those who win start to cry, and those who did not get a trophy try to pretend that they are ... [Read more...]

A friend asked me this morning if there was a way to plot a symbol in R (as a plotting character) representing a half-filled circle. I didn't know, but I figured this out (perhaps it's demonstrated elsewhere -- the ability to use Unicode symbols was added in 2008 or so -- ... [Read more...]

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Recently, Kevin Ummel gave a short conference about his PhD research at the Sustainable futures – Tyndall Centre researchers’ international conference. His work, named “Optimizing worldwide deployment of wind and solar power technologies via a high resolution, linear programming model”, is built with R. He is using the solaR package for ... [Read more...]

Although the official deadline is long past, I just became aware of this call for a postdoctoral position in Paris starting next Fall. Please feel free to apply: Summary Adaptive Markov Chain Monte Carlo (MCMC) methods are currently a very active field of research. MCMC methods are sampling methods, based ... [Read more...]

Are you a non-windows user wanting to share your R package with others who do use windows? There's a handy utility (http://win-builder.r-project.org/)that allows you to upload your .tar.gz file and it checks it, builds it, and sends you a link to downl... [Read more...]

(The examples here work with the version of insidefunctor tagged as "v1") I ran into an interesting problem using "inside" functors. Something is wrong in the following code (well, depending on what you thought it should do). __ library(insidefunctor) __ `%+.%` = fmap(`+`) __ x = seq(0, 10, len = 50) __ plot(x, collect(each(x) %+.% runif(1))) It's ... [Read more...]

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The solar irradiance incident outside the earth’s atmosphere is called the extraterrestial or extra-atmospheric irradiance. It is derived from the solar constant only with geometric equations. It can be easily calculated with the calcSol function of the solaR package. With this post I will show an example with some ... [Read more...]

No “That” Left Behind? I came across a post on Language Log last week giving some evidence that Obama tends to add that to the prepared version of his speeches. For example, in a recent speech at George Washington University, … Continue reading → [Read more...]

Gompertz Model Visualization # Gomperz growth function gomp [Read more...]