Monthly Archives: February 2010

Artificial Immune Systems and Financial Applications?

February 11, 2010
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Artificial Immune Systems and Financial Applications?

One of the buzzwords that seems to be common these days is AIS or Artificial Immune Systems. It is a biologically inspired classification type system that essentially tries to replicate some of our own natural immune system algorithms. Our bodies hav...

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Running totals in R

February 11, 2010
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Running totals in R

Learn about the cumsum function in R for running totals

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Using J48 Decision Tree Classifier to Dynamically Allocate Next Day Position in Stocks or Bonds

February 11, 2010
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Using J48 Decision Tree Classifier to Dynamically Allocate Next Day Position in Stocks or Bonds

The prior introduction using a simple model to determine next weeks change based on the S&P 500 index and VIX did not look very promising, although hopefully it served to familiarize yourself with how classification is used in augmenting trading decisi...

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Two New Soils-Related KMZ Demos

February 10, 2010
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Two New Soils-Related KMZ Demos

LCC KMZ Soil Texture KMZ   Forgot to post these KMZ files: 1-km scale, aggregate LCC and soil texture data, derived from SSURGO. These are part of a series of KMZ / raster...

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Video: What is R?

February 10, 2010
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By popular demand, we've made the video of our 30-minute webcast "The R Project" available on YouTube so that everyone can easily watch it. If you (or a friend!) have ever wondered what this R thing is all about, this is the video for you. Here's the first part: Because of YouTube restrictions it's split up into four parts,...

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Loglinear models using R

February 10, 2010
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Loglinear models using R

For those sociologists who want to estimate complicated loglinear models (e.g. Goodman's RC model) using R, the package "VGAM" seems to be a good choice.

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Speeding up simulations with Amazon EC2

February 10, 2010
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Over at Cerebral Mastication, JD Long tells a characteristically entertaining and informative story about how he uses R to run stochastic simulations of insurance portfolios and reinsurance treaties. A typical job involves 10,000 simulations, and when each estimate takes over 20 seconds you're talking some serious time to get the job done. Fortunately, this is the kind of problem...

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LocusZoom: Plot regional association results from GWAS

February 10, 2010
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Update Friday, May 14, 2010: See this newer post on LocusZoom. If you caught Cristen Willer's seminar here a few weeks ago you saw several beautiful figures in the style of a manhattan plot, but zoomed in around a region of interest, with several ot...

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Easy way of determining number of lines/records in a given large file using R

February 10, 2010
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Dear Readers,Today I would like to post the easy way of determining number of lines/records in any given large file using R.Directly to point.1) If data set is small let say less than 50MB or around in R one can read it with ease using: length(readLines("xyzfile.csv"))2) But if data set is too large say more...

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Easy way of determining number of lines/records in a given large file using R

February 10, 2010
By

Dear Readers,Today I would like to post the easy way of determining number of lines/records in any given large file using R.Directly to point.1) If data set is small let say less than 50MB or around in R one can read it with ease using: length(readLines("xyzfile.csv"))2) But if data set is too large say more...

Read more »