4342 search results for "git"

Another Experiment with R and Sweave

February 12, 2013
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The R package PApages is a great start towards addressing the very common problem of internal and external reporting in the money management industry.  Advent's APX, Axys, and Black Diamond and the up and coming extremely well-connected and well-f...

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The Problem with Testing for Heteroskedasticity in Probit Models

February 12, 2013
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The Problem with Testing for Heteroskedasticity in Probit Models

A friend recently asked whether I trusted the inferences from heteroskedastic probit models. I said no, because the heteroskedastic probit does not allow a researcher to distinguish between non-constant variance and a mis-specified mean function. In particular, my friend had a hypothesis that the variance of the latent outcome (commonly called "y-star") should increase with an

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Cluster Portfolio Allocation

February 11, 2013
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Cluster Portfolio Allocation

Today, I want to continue with clustering theme and show how the portfolio weights are determined in the Cluster Portfolio Allocation method. One example of the Cluster Portfolio Allocation method is Cluster Risk Parity (Varadi, Kapler, 2012). The Cluster Portfolio Allocation method has 3 steps: Create Clusters Allocate funds within each Cluster Allocate funds across

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US unemployment rates by State 1981-2011

February 11, 2013
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File under: getting data.Oh the irony. Exactly one day after I start to read the great book on Open Government by O'Reilly media (which they released in tribute to Aaron Schwartz), I come in need of time series data on unemployment rates in the United ...

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analyze health professional shortage areas (hpsa) with r

February 11, 2013
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a health professional shortage area (hpsa) is a geographic area, population group, or health care facility that has been designated by the united states government as having an insufficient supply of medical providers, based on certain provider-to-popu...

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Using R: accessing PANTHER classifications

February 10, 2013
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Using R: accessing PANTHER classifications

Importing, subsetting, merging and exporting various text files with annotation (in the wide sense, i.e. anything that might help when interpreting your experiment) is not computation and it’s not biology either, but it’s housekeeping that needs to be done. Everyone has a weapon of choice for general-purpose scripting and mine is R. Yes, this is

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Publishing from R+knitr to WordPress

February 10, 2013
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Publishing from R+knitr to WordPress

Tal Galili asked a question on StackOverflow on publishing blog posts to WordPress from R + knitr. William K. Morris has written a solution long time ago, and I tweaked it a little bit and created a function knit2wp() in the development version of knit...

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Happy Birthday Florence Henderson

February 9, 2013
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Happy Birthday Florence Henderson

As a celebration of Florence Henderson’s 79th birthday (on February 14), I have created this scatterplot to use in my regression course. The plot depicts the relationship between time spent on mathematics homework outside of school (expressed as z-scores) and … Continue reading →

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Introduction to Shiny Slides

February 9, 2013
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Below you can download the slides presented on February 9, 2013 at the Dallas R Users Group on RStudio’s Shiny framework which allows you to create interactive web applications in R. No knowledge of HTML or JavaScript is required! I introduce the alternatives and history of R programming on the web, the reactive programming model,

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PID Control-R

February 8, 2013
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PID Control-R

On a whim, I thought it might be fun to try to implement a PID control algorithm ... in R.Yes, I know I have a strange idea of fun.BackgroundPID control is a heuristic method of automatically controlling processes as wide ranging as water levels in tan...

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