Monthly Archives: March 2011

Ascii code table in R

March 8, 2011
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A quick method to enumerate the printable ascii characters with their hex & decimal values.The following code relies on taking the "raw" value of a base 10 int (this gives a hex value), and then using the builtin function rawToChar, which gives a character. You can of course change the range (up to 255). Not sure and haven't tested,...

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Can one beat a Random Walk– IMPOSSIBLE (you say?)

March 8, 2011
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Can one beat a Random Walk– IMPOSSIBLE (you say?)

Firstly, apologies for the long absence as I've been busy with a few things.  Secondly, apologies for the horrific use of caps in the title (for the grammar monitors).  Certainly, you'll gain something useful from today's musing, as it's a pr...

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Challenge: Visualizing the US Federal Budget

March 8, 2011
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Google today announced a Data Visualization Challenge that is well suited to the graphical capabilities of R. The goal is to visualize the US Federal budget from the point of view of the taxes an individual pays. The data are available from whatwepayfor.com -- their FAQ gives details about the source of the data and the philosophy of making...

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New R IDE

March 8, 2011
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New R IDE

I'm always looking for ways to improve my workflow and overall academic efficiency. I've tried a variety of text editors, GUIs, and integrated development environments (IDEs) for R. I have some preferences but I haven't found anything that I'm complete...

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A Short Return to the Age-Earnings Profile

March 8, 2011
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A Short Return to the Age-Earnings Profile

Two posts ago I mentioned the age-earnings profile but did not provide a regression of log earnings on wage. I also offered, without evidence, that fitting a simple linear regression would be inappropriate. How do I know that? How could … Continue reading →

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Splitting a Dataset Revisited: Keeping Covariates Balanced Between Splits

March 8, 2011
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Splitting a Dataset Revisited: Keeping Covariates Balanced Between Splits

In my previous post I showed you how to randomly split up a dataset into training and testing datasets. (Thanks to all those who emailed me or left comments letting me know that this could be done using other means. As things go with R, it's sometimes ...

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Splitting a Dataset Revisited: Keeping Covariates Balanced Between Splits

March 8, 2011
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In my previous post I showed you how to randomly split up a dataset into training and testing datasets. (Thanks to all those who emailed me or left comments letting me know that this could be done using other means. As things go with R, it's sometimes ...

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Blackbox trading Strategy using Rapidminer and R II

March 8, 2011
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Blackbox trading Strategy using Rapidminer and R II

Long time without updating the blog for lack of time (again) due to new professional and personal challenges. Continuing with the strategy of Black Box, thanks to recommendations made by several readers and the lack of time to make a good tutorial of the model, I’m going to make available the file with...

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Blackbox trading Strategy using Rapidminer and R II

March 8, 2011
By
Blackbox trading Strategy using Rapidminer and R II

Long time without updating the blog for lack of time (again) due to new professional and personal challenges. Continuing with the strategy of Black Box, thanks to recommendations made by several readers and the lack of time to make a good tutorial of the model, I’m going to make available the file with...

Read more »

R Studio

March 8, 2011
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R Studio

                      If you think that R is The EnvironmentForStatisticalAnalysisAndGraphics but you do not think that Vim is The Editor for text files you might want to have a look at R Studio. It works on Windows, MacOS and Linux. I tried it out on my Ubuntu

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