4145 search results for "git"

Sector Rotation Back Test Shiny web application

February 18, 2013
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Sector Rotation Back Test Shiny web application

Today, I want to share the Sector Rotation Back Test application (code at GitHub). This is the last application in the series of examples (I have shared 5 examples) that will demonstrate the amazing Shiny framework and Systematic Investor Toolbox to analyze stocks, make back-tests, and create summary reports. The motivation for this series of

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Data fishing: R and XML part 3

February 18, 2013
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Data fishing: R and XML part 3

I’ve recently posted two blogs about gathering data from web pages using functions in R. Both examples showed how we can create our own custom functions to gather data about Minnesota lakes from the Lakefinder website. The first post was an example showing the use of R to create our own custom functions to get

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Predictors, responses and residuals: What really needs to be normally distributed?

February 18, 2013
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Predictors, responses and residuals: What really needs to be normally distributed?

Introduction Many scientists are concerned about normality or non-normality of variables in statistical analyses. The following and similar sentiments are often expressed, published or taught: "If you want to do statistics, then everything needs to be normally distributed." "We normalized…Read more →

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Reshaping Horse Import/Export Data to Fit a Sankey Diagram

February 18, 2013
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Reshaping Horse Import/Export Data to Fit a Sankey Diagram

As the food labeling and substituted horsemeat saga rolls on, I’ve been surprised at how little use has been made of “data” to put the structure of the food chain into some sort of context* (or maybe I’ve just missed those stories?). One place that can almost always be guaranteed to post a few related

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Change fonts in ggplot2, and create xkcd style graphs

February 17, 2013
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Change fonts in ggplot2, and create xkcd style graphs

Installing and changing fonts in your plots comes now easy with the extrafonts-package. There is a excellent tutorial on the extrafonts github site, still I will shortly demonstrate how it worked for me. First, install the package and load it. You can now install the desired system fonts (at the moment only TrueType fonts): The

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Run production, one team at a time

February 17, 2013
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In a previous post, I used R to process data from the Lahman database to calculate index values that compare a team's run production to the league average for that year.  For the purpose of that exercise, I started the sequence at 1947, but for what follows I re-ran the code with the time period...

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A look at strucchange and segmented

February 17, 2013
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A look at strucchange and segmented

After last week's post it was commented that strucchange and segmented would be more suitable for my purpose. I had a look at both. Strucchange can find a jump in a time series, which was what I was looking for. In contrast segmented is more suitable f...

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Contribute to The R Journal with LyX/knitr

February 17, 2013
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Contribute to The R Journal with LyX/knitr

(This paragraph is pure rant; feel free to skip it) I have been looking forward to the one-column LaTeX style of The R Journal, and it has arrived eventually. Last time I mentioned "it does not make sense to sell the cooked shrimps"; actually there is ...

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Gist for previous posts

February 17, 2013
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The more I use it, the more I understand the benefits and value of Github as a code-sharing resource. The gist found here is the R code for my posts on run scoring trends by league (found here, here, and here).  I will continue to use Github for t...

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Interactive stage-structured population model

February 16, 2013
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Interactive stage-structured population model

This is an example of interfacing R and shiny to allow users to explore a biological model often encountered in an introductory ecology class. We are interested the growth of a population that is composed of multiple, discrete stages or age classes. Patrick H. Leslie provides an in-depth derivation of the model in his 1945 paper “On the...

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