Monthly Archives: August 2011

Amazon Machine Image Created With RTextTools Pre-installed

We recently created an AMI for Amazon's EC2 cloud computing service. Users with AWS accounts can access the public AMI by searching ami-817eb8e8. The AMI is based off of Drew Conway's excellent AMI, but with R 2.13 loaded and RTextTools and

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What makes a hockey Hall-of-Famer?

August 9, 2011
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What makes a hockey Hall-of-Famer?

At the JSM conference last week, I stopped by a great poster by Steve Salaga and Brian Mills, graduate students at University of Michigan's Department of Sport Management. The guys were clearly hockey fans, and had channelled their enthusiasm for a sport into an interesting statistical analysis of game and player data from the NHL. One analysis, based on...

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Estimate decay of linkage disequilibrium with distance

August 9, 2011
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Estimate decay of linkage disequilibrium with distance

It is well known that linkage disequilibrium (LD) decays with distance. Several functions have been proposed to estimate such decay. Among the most widely used are the Hill and Weir (1) formula for describing the decay of r2 and a formula proposed by Abecasis (2) for describing the decay of D’. I wrote R functions

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Forecasting recessions

August 9, 2011
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Forecasting recessions

John Hussman has a Recession Warning Composite that I am attempting to replicate/improve. The underlying data seems to be easy enough to get from FRED using the quantmod package in R. I don't quite understand the index Hussman is using for commercial...

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The indices understate the carnage

August 9, 2011
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The indices understate the carnage

The first 6 trading days of August have been bad for the major indices, but how variable is that across portfolios? To answer that, two sets of random portfolios were generated from the constituents of the S&P 500.¬† The trading days are 2011 August 1 — 5 and 8. The returns of the indices for … Continue reading...

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Blog planets are like conferences… (aka R-bloggers.com)

August 8, 2011
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Blog planets are like conferences… (aka R-bloggers.com)

Blog planets are websites that aggregate blog feeds around a particular topic or project. It is probably called after one of its first implementations, the Planet software. These planets are like conferences, rather than journals. Like conferences with...

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Installing Rmpi with OpenMPI on Mac OS X Lion

August 8, 2011
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For whatever reason, Apple decided not to include OpenMPI in Mac OS X Lion (it was supported in Leopard and Snow Leopard). I found this out the hard way after doing a clean install of Lion. Here are steps to install OpenMPI and get it working with the Rmpi package in R. One benefit of

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How ANZ uses R for credit risk analysis

August 8, 2011
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How ANZ uses R for credit risk analysis

At last month's R user group meeting in Melbourne, the theme was "Experiences with using SAS and R in insurance and banking". There, Hong Ooi from ANZ (Australia and New Zealand Banking Group) gave a presentation on "Experiences with using R in credit risk". I didn't get to see the presentation myself, but the slides tell a great story...

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FII and DII turnover with effect on Nifty Downloader

August 8, 2011
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FII and DII turnover with effect on Nifty Downloader

My thirst for statistics has been increasing. IV had another requirement, which would eventually be useful to me as well. He currently downloads FII and DII buy and sell values and its impact on Nifty manually in Excel. He suggested me to try and autom...

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Power of running world records

August 8, 2011
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Power of running world records

Followinga few entries on sports here and there, I was wondering what kind of law follow the running records with respect to the distance. The data are available on Wikipedia, or here for a tidied version. It collects 18 distances, from 100 meters to 100 kilometers. A log-log scale is in order: It is nice

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