5235 search results for "git"

Running Back-tests in parallel

November 11, 2013
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Running Back-tests in parallel

Once you start experimenting with many different asset allocation algorithms, the computation time of running the back-tests can be substantial. One simple way to solve the computation time problem is to run the back-tests in parallel. I.e. if the asset allocation algorithm does not use the prior period holdings to make decision about current allocation,

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Merge Relational Dataframes

November 11, 2013
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Merge Relational Dataframes

A Question Recently, a student, working on her Senior Thesis at Northland College, asked me the following question: Attached is an Excel file with three “important to R” worksheets. The only thing that connects all 3 worksheets is the Lift.ID … Continue reading →

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Imperialstan

November 11, 2013
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Imperialstan

Despite the map here, I'm not going to talk about yet another fraction of the former Soviet Empire which is taken the form of a people's republic, possibly with witty British Ambassadors.In fact, I'm going to talk about the Stan workshop that I have be...

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Quick tip on controlling log output in tests

November 11, 2013
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Quick tip on controlling log output in tests

When running tests for a package, it’s important that the console output is unadulterated since test results are printed with …Continue reading »

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cMDS: visualising changing distances

November 11, 2013
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cMDS: visualising changing distances

Gina Gruenhage has just arxived a new paper describing an algorithm we call cMDS. Here’s what it’s for: if you do any kind of data analysis you often find yourself comparing datapoints using some kind of distance metric. All’s well if you have a unique reasonable distance metric you can use, but often what you

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Extracting standard errors and treatment effects from medical journal tables (powered by R)

November 10, 2013
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Extracting standard errors and treatment effects from medical journal tables (powered by R)

I decided to start blogging the R code used for some of my statistical posts, so I will start with the meta-analysis posts and move on to more difficult stuff. As stated previously (here and here) the problem is to convert the reported relative risks(RR, ), 95% confidence interval () and p-value () into estimates

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What’s in my Pocket? (Part II) – Analysis of Pocket App Article Tagging

November 10, 2013
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What’s in my Pocket? (Part II) – Analysis of Pocket App Article Tagging

IntroductionYou know what's still awesome? Pocket.As I noted in an earlier post (oh god, was that really more than a year ago?!) I started using the Pocket application, previously known as Read It Later, in July of 2011 and it has changed my readi...

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Hurricanes in South Carolina

November 10, 2013
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Hurricanes in South Carolina

In a recent post, I discussed the occurrence of hurricanes in the North Atlantic basin. The data comes from the National Oceanic and Atmospheric Association, a member of the US federal government. The data spans a bit more than 150 years. In that post, I make the observation that the data supports a model wherein

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A small comparison of bio-equivalence calculations.

November 10, 2013
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Last week I looked at two-way cross-over studies and followed the example of Schütz (http://bebac.at/) in the analysis. Since the EU has its on opinions (Questions & Answers: Positions on specific questions addressed to the pharmacokinetics working party) and two example data sets, I was wondering how the various computations compared.Data There...

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Towards the R package sheldus: Part 2: Losses from Natural Disasters in the US

November 9, 2013
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In my earlier post I summarized the work on my upcoming R package on the SHELDUS database. This is a database on human and property losses from natural disasters in the United States. Although the data is free, downloading the data is tedious and ...

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