3972 search results for "git"

Who are the pollinators? (with R plot)

December 17, 2012
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Who are the pollinators? (with R plot)

I’ve been dreaming on writing a manuscript about who are the pollinators for a while, but it looks I’m not going to have the time soon, so here is an early draft of what the main figure should look like: It’s surprisingly … Continue reading →

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analyze the behavioral risk factor surveillance system (brfss) with r and monetdb

December 17, 2012
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experimental.  the behavioral risk factor surveillance system (brfss) aggregates behavioral health data from 400,000 adults via telephone every year.  it's um *clears throat* the largest telephone survey in the world and it's gotta lotta uses...

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The Inverse Herfindahl–Hirschman Index as an “Effective Number of” Parties

December 17, 2012
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The Inverse Herfindahl–Hirschman Index as an “Effective Number of” Parties

I learned of the passing of Albert Hirschman on December 11, and while better and more instructive tributes to his life can be read elsewhere, I wanted to focus on a little piece of Hirschman’s work that I use all the time: the (inverse) Herfindahl–Hirschman Index. The HHI is basically a measure of market concentration, but...

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A look at historical Value at Risk

December 17, 2012
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A look at historical Value at Risk

Historical Value at Risk (VaR) is very popular because it is easy and intuitive: use the empirical distribution of some specific number of past returns for the portfolio. Previously “The estimation of Value at Risk and Expected Shortfall” included an R function to estimate historical VaR. Generating portfolios A useful tool to explore risk models … Continue reading...

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The Eye of the World as word cloud

December 16, 2012
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The Eye of the World as word cloud

The Eye of the World is the first book of Robert Jordan's Wheel of Time books. As the last of these books will be published soon, I was wondering if natural language processing can be used to examine books like these. For this purpose I downloaded a co...

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Possibly slightly better text analysis with lme4

December 16, 2012
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Possibly slightly better text analysis with lme4

lme4 and its cousin arm are extremely useful for a huge variety of modeling applications (see Gelman and Hill’s book), but today we’re going to do something a little frivolous with them. Namely, we’re going to extend our Denver Debat...

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Building R packages: missing path to pdflatex

December 15, 2012
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Building R packages: missing path to pdflatex

Recently whiling trying to build an R package for generalized estimating equation model selection (QICpack on github), I was getting an error related to latex creating the PDF package manuals. It seems like this is a relatively common problem on … Continue reading →

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Text analysis made too easy with the tm package

December 15, 2012
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Text analysis made too easy with the tm package

Today’s Gist takes the CNN transcript of the Denver Presidential Debate, converts paragraphs into a document-term matrix, and does the absolute most basic form of text analysis: a raw word count. There are actually quite a few steps in this proc...

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Le Monde puzzle (#800)

December 14, 2012
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Le Monde puzzle (#800)

Here is the mathematical puzzle of the weekend edition of Le Monde: Consider a sequence where the initial number is between 1 and 10³, and each term in the sequence is derived from the previous term as follows: if the last digit of the previous term is between 6 and 9, multiply it by 9;

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d3, Shiny, and R Reporting Performance

December 14, 2012
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d3, Shiny, and R Reporting Performance

I thought it would be interesting to offer a little different example of how we can use d3, R, and Rstudio Shiny.  This time we will offer a simple example to report portfolio or index performance.  Just as a test of my progress, I also threw...

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