1220 search results for "tutorial"

Support Vector Machine with GPU, Part II

October 21, 2011
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Support Vector Machine with GPU, Part II

In our last tutorial on SVM training with GPU, we mentioned a necessary step to pre-scale the data with rpusvm-scale, and to reverse scaling the prediction outcome. This cumbersome procedure is now simplified with the latest RPUSVM. read more

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Geo-doodlers – Paul Butler and FlowingData

October 16, 2011
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Geo-doodlers – Paul Butler and FlowingData

I found this great R-Visualization example via an R-Blogger post that xingmowang made. (One more good reason for why it is important to read lots of field-related blogs!)Here's the image:If this was merely eye-candy, I would have enjoyed it, but not in...

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Principal component analysis : Use extended to Financial economics : Part 1

October 15, 2011
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Principal component analysis : Use extended to Financial economics : Part 1

While working for my Financial economics project I came across this elegant tool called Principal component analysis (PCA)which is an extremely powerful tool when it comes to reducing the dimentionality of a data set comprising of highly correlated var...

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R related books: Traditional vs online publishing

October 12, 2011
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R related books: Traditional vs online publishing

How many R related books have been published so far? Who is the most popular publisher? How many other manuals, tutorials and books have been published online? Let's find out. A few years ago I used the publication list on r-project.org as an argument ...

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Calculating and graphing within-subject confidence intervals for ANOVA

October 4, 2011
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Calculating and graphing within-subject confidence intervals for ANOVA

Psychologists are gradually coming round to the view that it is a good idea to present interval estimates alongside point estimates of statistics. The most common statistic reported in psychology research is almost certainly the mean (strictly...

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Reminder: One week til Rcpp class in San Francisco

October 1, 2011
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Just a quick note to remind everyone that the Rcpp class in San Francisco, which I am holding together with Revolution Analytics, will take place a week from today. We are happy to report that the number of registrations has met our initial target...

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Simulation studies in R – Using all cores and other tips

September 16, 2011
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After working more seriously with simulations I noticed some updates were necessary to my previous setup. Most notably are the following three: It is very handy to explicitly call the different scenarios instead of using nested loops Storing intermediate results in single files obliviates the need to rerun an almost finished but crashed analysis and

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How to program MapReduce jobs in Hadoop with R

September 13, 2011
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MapReduce is a powerful programming framework for efficiently processing very large amounts of data stored in the Hadoop distributed filesystem. But while several programming frameworks for Hadoop exist, few are tuned to the needs of data analysts who typically work in the R environment as opposed to general-purpose languages like Java. That's why the dev team at Revolution Analytics...

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Alternately coloured line environment with fancyvrb

September 11, 2011
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Recently, while typing up an R tutorial, I used the LaTeX fancyvrb package to create two environments—one coloured blue for R commands, and one coloured red to display R output. This worked well for large blocks of each type. Then I decided I wan...

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A simple example for writting parallel code

September 7, 2011
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A simple example for writting parallel code

Today, programmers have to deal with multi-core and multi-computer technologies. Several people claim that software developers are far behind hardware technologies. My two favorite posts for this statement are Editor’s Desk: Software Lags Behind Hardware, But That’s a Good Thing A Hacker’s Craic -Why is software so far behind hardware? Parallel computing is not that

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