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ARMA Models for Trading, Part III

May 2, 2011
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ARMA Models for Trading, Part III

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 is the daily returns) then

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Sustainable Futures conference in Manchester

Sustainable Futures conference in Manchester

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 the solar irradiance calculations,

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Postdoc on adaptive MCMC in Paris

May 2, 2011
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Postdoc on adaptive MCMC in Paris

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 on Markov Chains which are

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Here comes the sun

Here comes the sun

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 packages from the Spatial task view.

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Bayesian Confidence Intervals: Obama’s ‘That’-Addition and Informality

May 1, 2011
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Bayesian Confidence Intervals: Obama’s ‘That’-Addition and Informality

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 →

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Friday function triple bill: with vs. within vs. transform

April 29, 2011
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Friday function triple bill: with vs. within vs. transform

When you first learnt about data frames in R, I’m sure that, like me, you thought “This is a lot of hassle having to type the names of data frames over and over in order to access each column”. library(MASS) anorexia$wtDiff <- anorexia$Postwt - anorexia$Prewt #I have to type anorexia how many times? Indeed, any

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RStudio is good for you

April 29, 2011
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RStudio is good for you

I was recently introduced to RStudio, a new integrated development environment for R, it is just amazing! It is free, and open, compatible with PC/Mac/Linux OSs. You can also choose to run it in the cloud, and access it from your favorite web browser. As you can see, the window divides into four in a

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Data Aggregation in R: plyr, sqldf and data.table

April 28, 2011
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Data Aggregation in R: plyr, sqldf and data.table

I’ve also previously put up a couple of posts about aggregating data in R. In this post, I’m going to be trying some other alternative methods for aggregating the dataset. Before I begin, I’d like to thank Matthew Dowle for highlighting these to me. It’s a bit daunting at first, deciding which method of aggregating data is

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“Inside” Functors — Multiple Arguments

April 27, 2011
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“Inside” Functors — Multiple Arguments

Again for HTML reasons this has been taken to http://strugglingthroughproblems.blogspot.com/2011/04/inside-functors-multiple-arguments.html

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“Inside” Functors

April 26, 2011
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“Inside” Functors

So, WordPress doesn’t like RweaveHTML, so this is posted at http://strugglingthroughproblems.blogspot.com/2011/04/inside-functors.html

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