3880 search results for "git"

analyze the area resource file (arf) with r

October 1, 2012
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the arf is fun to say out loud.  it's also a single county-level data table with about 6,000 variables, produced by the united states health services and resources administration (hrsa).  the file contains health information and statistics fo...

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Where in the world is R and RStudio

October 1, 2012
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Where in the world is R and RStudio

Using the web logs collected when users download RStudio, we’ve prepared the following two maps showing where RStudio is being used, over the whole globe and just within the continental USA. Obviously this data is somewhat biased, as it reflects the number of downloads of RStudio, rather than the number of users of R (which

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Example 10.4: Multiple comparisons and confidence limits

October 1, 2012
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Example 10.4: Multiple comparisons and confidence limits

A colleague is a devotee of confidence intervals. To him, the CI have the magical property that they are immune to the multiple comparison problem-- in other words, he feels its OK to look at a bunch of 95% CI and focus on the ones that appear to exclude the null. This though...

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When Russell 2000 is Low Vol

October 1, 2012
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When Russell 2000 is Low Vol

Continuing in my exploration of the Russell 2000 (Russell 2000 Softail Fat Boy), I thought I would try to approach the topic with a low volatility paradox mindset.  Since 2005, beta of the Russell 2000 compared to the S&P 500 has exceeded 1.2 ...

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Making random, equally-sized partitions

October 1, 2012
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Making random, equally-sized partitions

Sometimes, as with cross-validation, one needs to generate k partitions, each with an equal number of observations. There are probably an infinite number of ways this could be done in R, but the Gist below illustrates one way to do it in four lines, w...

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Working with Bipartite/Affiliation Network Data in R

September 30, 2012
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Working with Bipartite/Affiliation Network Data in R

Data can often be usefully conceptualized in terms affiliations between people (or other key data entities). It might be useful analyze common group membership, common purchasing decisions, or common patterns of behavior. This post introduces bipartite/affiliation network data and provides … Continue reading →

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Football, an ordinal model

September 30, 2012
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Football, an ordinal model

On September 19th, flo2speak remarked under a post that his/her experience is that ordinal models had better performance. That seems reason enough to try, so there we are. In examining this type of model it is found that more complex models can be...

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Plot R Data With googleVis

September 30, 2012
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Here is a little code snippet that shows how to do two things Use the Google Maps API to resolve place names into lat-long coordinate pairs. Plot R dataframes that contain lat-long data (for example from #1) onto Google Maps for quick visualization using the googleVis package.  The embedded map looks a little wonky here but it looks...

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Quantifying student feedback using Org mode and R

September 30, 2012
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Quantifying student feedback using Org mode and R

As the term has progressed, my LSM2241 lectures are getting more consistent. I’m aiming to use 45 slides for what is officially a two hour lecture, although in reality it lasts about 90 minutes. We take a break at about 50 … Continue reading →

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Weekend Reading – Gold in October

September 28, 2012
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Weekend Reading – Gold in October

I recently came across the “An early Halloween for gold traders” article by Mark Hulbert. I have discussed this type of seasonality analysis in my presentation at R/Finance this year. It is very easy to run the seasonality analysis using the Systematic Investor Toolbox. This confirms that October have been historically bad for Gold, but

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