2148 search results for "MAP"

Because it’s Friday: Spurious correlation edition

August 26, 2011
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Because it’s Friday: Spurious correlation edition

If the Flight of the Concords taught me anything, it's that you can't trust Australians. This morning I was poking around the DataMarket site, when I noticed something suspicious about Australian sheep production: I decided to investigate further: ju...

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Quick labels within figures

August 26, 2011
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Quick labels within figures

One of the coolest R packages I heard about at the useR! Conference: Toby Dylan Hocking‘s directlabels package for putting labels directly next to the relevant curves or point clouds in a figure. I think I first learned about this idea from Andrew Gelman: that a separate legend requires a lot of back-and-forth glances, so

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Examples on Clustering with R

August 25, 2011
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Examples on Clustering with R

R code examples on various clustering techniques are available as “Clustering in R” in Chapter 4 of R & Bioconductor Manual by Thomas Girke, UC Riverside. It provides R examples on - Hierarchical Clustering, including tree cutting/coloring and heatmaps, - … Continue reading →

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"My interpretation of [Leland Wilkinson’s] grammar [of statistical graphics]: —Data is the most…"

August 25, 2011
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"My interpretation of [Leland Wilkinson’s] grammar [of statistical graphics]: —Data is the most…"

“My interpretation of grammar : —Data is the most important thing, and the thing that you bring to the table. —Geometric objects … what you actually see on the plot: points, lines, polygons, etc. ...

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"My interpretation of [Leland Wilkinson’s] grammar [of statistical graphics]: —Data is the most…"

August 25, 2011
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"My interpretation of [Leland Wilkinson’s] grammar [of statistical graphics]:
—Data is the most…"

“My interpretation of grammar : —Data is the most important thing, and the thing that you bring to the table. —Geometric objects … what you actually see on the plot: points, lines, polygons, etc. ...

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Comparison of ave, ddply and data.table

August 25, 2011
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Comparison of ave, ddply and data.table

A guest post by Paul Hiemstra. ———— Fortran and C programmers often say that interpreted languages like R are nice and all, but lack in terms of speed. How fast something works in R greatly depends on how it is implemented, i.e. which packages/functions does one use. A prime example, which shows up regularly on

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The Open Governance Index: Results for The R Project

August 24, 2011
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Just over two weeks ago, I invited readers to complete the Open Governance Index (OGI) Questionnaire regarding The R Project. The OGI evaluates several facets of governance in open source projects (OGI publication). The OGI questionnaire is reproduced below, and each question is linked from the table of useR responses. The table below presents the

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Graphically analyzing variable interactions in R

August 23, 2011
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Graphically analyzing variable interactions in R

I studied Ecology as an undergraduate, which meant I spent a lot of time gathering and analyzing field data. One of the basic tools we used to look for relationships in a large set of variables was correlation and scatterplot matrices. Each of these ...

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Recession forecasting II: Assessing Hussman’s Accuracy

August 22, 2011
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Recession forecasting II: Assessing Hussman’s Accuracy

In my last post on recessions, I implemented John Hussman's Recession Warning Composite in R. In this post I will examine how well this index performs and discuss how we might improve it. If you would like to follow along at home, be sure to run the ...

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The performance cost of a for-loop, and some alternatives

August 21, 2011
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I’ve recently been spending a lot of time running various simulations in R. Because I often use snow to perform simulations across several computers/cores, results typically come back in the form of a list object. Summarizing the results from a list … Continue reading →

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