2447 search results for "gis"

Pre-processing text: R/tm vs. python/NLTK

February 16, 2011
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Pre-processing text: R/tm vs. python/NLTK

  Let’s say that you want to take a set of documents and apply a computational linguistic technique.  If your method is based on the bag-of-words model, you probably need to pre-process these documents first by segmenting, tokenizing, stripping, stopwording, and … Continue reading →

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ABC in London

February 15, 2011
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ABC in London

After the very exciting and I think quite successful ABC in Paris meeting two years ago, Michael Stumpf from Imperial College London suggested a second edition in London along the same lines. Michael kindly associated me with the planning of this meeting. It is (logically) called ABC in London (or ABCiL) and will take place

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R 2.12.2 scheduled for February 25

February 15, 2011
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The next release of R is scheduled for release February 25, and R 2.12.2 will likely be the final bug-fix release of the 2.12 series before R 2.13 is released in April. According to the NEWS file in the latest daily build, 2.12.2 will improve complex-arithmetic support on some rare platforms that don't support complex types in C99, and...

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Visualize NHL Play-by-Play using Tableau Public and R

February 13, 2011
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Visualize NHL Play-by-Play using Tableau Public and R

Nothing like a little Sunday morning data hacking before a big game!  I have been wanting to play with the NHL play-by-play event files for some time now.  The JSON datasets provide a wealth of information about each event in the game including the location, as defined by the fields xcoord and ycoord. I am

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Stata or R

February 10, 2011
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Stata or R

Recently I came across a complex model written in Access with complex SQL queries all over the place. The engineer who was maintaining it and I did some analysis and agreed that the model was using SQL in an unnatural way (things SQL isn't good at) - c...

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Stata or R

February 10, 2011
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Stata or R

Recently I came across a complex model written in Access with complex SQL queries all over the place. The engineer who was maintaining it and I did some analysis and agreed that the model was using SQL in an unnatural way (things SQL isn't good at) - c...

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Stationarity

February 9, 2011
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Stationarity

In time series work you often run into difficulties in modeling processes where the overall level of one variable (an input, for example) changes over time but the levels of another variable (an output) do not change. For instance if … Continue reading →

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Create a Web Crawler in R

February 8, 2011
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Create a Web Crawler in R

Admittedly I am not the best R coder, and I certainly have a lot to learn, but the code at the link below should provide you with an example of how easy it is to create a very (repeat: very) basic web crawler in R.  If you wanted to do this in SPSS, and I

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Utilizing multiple cores in R

February 8, 2011
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There are a couple of options in R, if you want to utilize multiple cores on your machine. These days my favorite is doMC package, which depends on foreach and multicore packages.in the section below squareroot for each number is calculated in parallel...

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Utilizing multiple cores in R

February 8, 2011
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There are a couple of options in R, if you want to utilize multiple cores on your machine. These days my favorite is doMC package, which depends on foreach and multicore packages.in the section below squareroot for each number is calculated in parallel...

Read more »