# Monthly Archives: December 2013

## 24 Days of R: Day 8

December 7, 2013
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I saved the data from the last post which shows the percentage of Republican voters in each county. In addition to that column, I also have figures from the 2010 census. This will show things like age, ethnicity, urbanization and home ownership. Those census figures show actual population counts, so they'll need to be altered

December 7, 2013
By

I saved the data from the last post which shows the percentage of Republican voters in each county. In addition to that column, I also have figures from the 2010 census. This will show things like age, ethnicity, urbanization and home ownership. Those census figures show actual population counts, so they’ll need to be altered to relative numbers to...

## R Interface for Teaching

R Interface for Teaching Kaitlin Thaney asked on Twitter last week about using Ramnath Vaidyanathan's new interactive R notebook 1 2 for teaching. Liking the look of interactive R notebook by @ramnath_vaidya. Any success stories in using to teach? http://t.co/wmVuFM2Rst (HT @_inundata)— Kaitlin Thaney (@kaythaney) July 9, 2013 Now, to be clear up front,...

## R and Big Data at Big Data Summit at UI Research Park

December 7, 2013
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I spent yesterday at the very enjoyable Big Data Summit held at the University of Illinois Research Park at the edge of the University of Illinois at Urbana-Champaign. campus. My (short) presentation was part of a panel session on R and Big Data...

## 24 Days of R: Day 7

December 7, 2013
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Carrying on from the last post, I'm going to take a closer look at election results for the 2012 US presidential election in North Carolina. This state's 15 electoral votes went to the Republican, Mitt Romney. On the US electoral college map, that means the state shows up as red. As I write this, I'm

## Random points on the Earth

December 7, 2013
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$n$

The problem with puzzles is that you keep it in your head for days, until you find an answer. Or at least some ideas about a possible answer. This is what happened to me a few weeks ago, when a colleague of mine asked me the following question : Consider points uniformly distributed on a sphere. What is the...

## An Animation of the t Distribution as a Mixture of Normals

December 7, 2013
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You’ve probably heard about the t distribution. One good use for this distribution is as an alternative to the normal distribution that is more robust against outliers. But where does the t distribution come from? One intuitive characterization of the t is as a mixture of normal distributions. More specifically, as a mixture of an infinite number of...

## Fall is the data analysis season

December 7, 2013
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Dear diary, I spent a lot of my summer in the lab, and my fall has been mostly data analysis, with a little writing and a couple of courses thrown in there. Data analysis means writing code, and nowadays I do most of my work with the help of R. R has even replaced python

## Using Samatha

Using Samatha So I decided to try out David Springates Samatha package for statically building this blog. If you decide to use it, be warned, right now it is a little rough around the edges, and needs some work. David created his own blog using it, and has been using that as a test case. Unfortunately, that has meant that...

December 6, 2013
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Mebane Faber posted another interesting blog post: Building a Simple Sector Rotation on Momentum and Trend that caught my interest. Today I want to show how you can test such strategy using the Systematic Investor Toolbox: Mebane thank you very much for sharing your great ideas. I would encourage readers to play with this strategy