Monthly Archives: June 2012

Getting numpy data into R

June 30, 2012
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The other day, I found myself confronted with a large number of large files. Which were presented in (gzip-)compressed ascii format---which R reads directly via gzfile() connections---as well as (compressed) numpy files.The numpy can be read very ...

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Fun with the googleVis Package for R

June 30, 2012
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Fun with the googleVis Package for R

Using packages such as ggplot and lattice can produce some great charts and visualization, but googleVis is tough to beat for interactive charts to share on the web. Click on the image below to open up the html page. This was all done in R! I will warn you that it is too easy to … Continue reading...

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R is fun

June 30, 2012
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As mentioned in Universal portfolio, part 6, the wealth reported in Table 8.4 of Universal Portfolios could not be reproduced.  An other observation is that the random weight vectors reported in Table 8.4 are shown in descending lex...

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Coefficient Plots in R

June 30, 2012
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One popular trend in presenting results is the "coefficient plot," an alternative to the table of regression coefficients. I am seeing this a little more often in political science research and have received a few requests for code, so I … Contin...

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Simple and heuristic optimization

June 29, 2012
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Simple and heuristic optimization

This week, at the Rmetrics conference, there has been an interesting discussion about heuristic optimization. The starting point was simple: in complex optimization problems (here we mean with a lot of local maxima, for instance), we do not ne...

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igraph and SNA: an amateur’s dabbling

June 29, 2012
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igraph and SNA: an amateur’s dabbling

I’ve been playing with the igraph package a bit lately (see previous post HERE) and wanted to approach a problem I once visited in the past. The basic gist of the problem is this: Students in a class are asked … Continue reading →

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SYTYCD — where are these terrific dancers come from?

June 29, 2012
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It’s Saturday midnight and I’m already sleepy. However, after several hours, I finally got this google geographic map embedded in my post. Aha!!! This is about 20 finalists from the 9th season of So You Think You Can Dance. I count the states … Continue reading →

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Simple and heuristic optimization

June 29, 2012
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Simple and heuristic optimization

This week, at the Rmetrics conference, there has been an interesting discussion about heuristic optimization. The starting point was simple: in complex optimization problems (here we mean with a lot of local maxima, for instance), we do not necessarily need extremely advanced algorithms that do converge extremly fast, if we cannot ensure that they reach the optimum. Converging extremely fast, with a...

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Wrap-up on Blogging with R Markdown and tumblr

June 29, 2012
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This is a wrap-up post to summarize a few of the issues I’ve found so far with blogging on tumblr with R Markdown.tumblr Puts a 1Mb Cap On Its HTML EditorFair warning.When I tried eating my own dogfood while writing the previous posts, I found that I had to manually upload all those pretty screenshots of the tumblr interface. For some...

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igraph and structured text exploration

June 29, 2012
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igraph and structured text exploration

I am in the slow process of developing a package to bridge structured text formats (i.e. classroom transcripts)  with the tons of great R packages that visualize and analyze quantitative data (If you care to play with a rough build … Continue reading →

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