2645 search results for "gis"

R is a cool sound editor!

September 7, 2011
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Capabilities of R are definitely unless! After my previous posts about some easy image editing in R (they are here, and here), now is the time to explore if R is capable of sound editing!Just for fun, here I created a function that receives a phone number (or another sequence of numbers), and returns the equivalent melody...

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Webinar: Leveraging R in Hadoop Environments

September 6, 2011
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Webinar: Leveraging R in Hadoop Environments

On Wednesday September 21, Revolution Analytics' CTO David Champagne will give a live webinar introducing three new open-source packages for R and Hadoop, which make it possible to work with Hadoop data in R, and bring in-database R analytics to Hadoop. Here are the details: Date: Wednesday, September 21st Time: 10:00AM - 10:30AM Pacific Time Presenter: David Champagne, Chief...

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Example 9.4: New stuff in SAS 9.3– MI FCS

September 6, 2011
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Example 9.4: New stuff in SAS 9.3– MI FCS

We begin the new academic year with a series of entries exploring new capabilities of SAS 9.3, and some functionality we haven't previously written about.We'll begin with multiple imputation. Here, SAS has previously been limited to multivariate norma...

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An example of ROC curves plotting with ROCR

September 3, 2011
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An example of ROC curves plotting with ROCR

Decided to start githib with ROC curve plotting example. There is not a one ROC curve but several - according to the number of comparisons (classifications), also legend with maximal and minimal ROC AUC are added to the plot. ROC curves and ROC AU...

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Fix missing dates with R

September 2, 2011
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Fix missing dates with R

I have data on user access to a website. This log file (helpdesk log.csv) just contains the date of access, and how many accesses were counted. It would look like this:Date hits13-07-2011 214-07-2011 116-07-2011 317-07-2011 4...As you can see, for day...

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Big Analytics: Closing the "clue gap" with Big Data

August 31, 2011
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There's been an growing discussion over the past couple of years on the topic of Big Data: how to deal with the situation when you have more data than can be conveniently managed and analyzed by traditional software tools. But Big Data has little intrinsic value in its own right: its value is only realized when you can deploy...

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R is a cool image editor #2: Dithering algorithms

August 29, 2011
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R is a cool image editor #2: Dithering algorithms

Here I implemented in R some dithering algorithms: - Floyd-Steinberg dithering - Bill Atkinson dithering - Jarvis-Judice-Ninke dithering - Sierra 2-4a dithering - Stucki dithering - Burkes dithering - Sierra2 dithering - Sierra3 dithering For each algorithm, I wrote a 2-dimensional convolution function (a matrix passing over a matrix); it is slow because I didn't implemented any fasting tricks. It can be easily implemented in C, then used...

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HPC for biological research

August 28, 2011
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In early May I had the opportunity to attend a workshop on using high performance computing in R hosted at Nimbios. I’ve been meaning to write a summary of the meeting ever since but got sidetracked by various other projects. Since a collaborator recently asked for meeting notes I finally took the time to write

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Real-time data collection and analysis in class

August 28, 2011
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Real-time data collection and analysis in class

As September draws nearer, my mind inevitably turns away from my lofty (and largely unmet) summer research goals, and toward teaching.  This semester I will be trying out a teaching technique using live data collection and analysis as a tool to encourage student engagement.  The idea is based on the electronic polling technology known as

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SIGKDD 2011 Conference — Days 2/3/4 Summary

August 27, 2011
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SIGKDD 2011 Conference — Days 2/3/4 Summary

<< My review of Day 1. I am summarizing all of the days together since each talk was short, and I was too exhausted to write a post after each day. Due to the broken-up schedule of the KDD sessions, I group everything together instead of switching back and forth among a dozen different topics. By far the most enjoyable...

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