Monthly Archives: March 2011

Visualizing the Language Used by Academics when Protected by Anonymity

March 7, 2011
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Those in the political science discipline probably remember their first encounter with poliscijobrumors.com. For those outside, you have probably never heard of this particular message board, and you would have no reason to. As the URL suggests, the board specializes in rumor, gossip, back-bitting, mudslinging, and the occasional lucid thread on the political science

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Example 8.29: Risk ratios and odds ratios

March 7, 2011
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Example 8.29: Risk ratios and odds ratios

When can you safely think of an odds ratio as being similar to a risk ratio?Many people find odds ratios hard to interpret, and thus would prefer to have risk ratios. In response to this, you can find several papers that purport to convert an odds rat...

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R Tutorial Series: ANOVA Pairwise Comparison Methods

March 7, 2011
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R Tutorial Series: ANOVA Pairwise Comparison Methods

When we have a statistically significant effect in ANOVA and an independent variable of more than two levels, we typically want to make follow-up comparisons. There are numerous methods for making pairwise comparisons and this tutorial will demonstrate...

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R Tutorial Series: ANOVA Pairwise Comparison Methods

March 7, 2011
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R Tutorial Series: ANOVA Pairwise Comparison Methods

When we have a statistically significant effect in ANOVA and an independent variable of more than two levels, we typically want to make follow-up comparisons. There are numerous methods for making pairwise comparisons and this tutorial will demonstrate...

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Factor models of variance in finance

March 7, 2011
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Factor models of variance in finance

In “What the hell is a variance matrix?” I talked about the basics of variance matrices and highlighted challenges for estimating them in finance.  Here we look more deeply at the most popular estimation technique. Models for variance matrices The types of variance estimates that are used in finance can be classified as: Sample estimate … Continue reading...

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R Package Automated Download

March 6, 2011
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There are situations where we might want to run R on a standalone machine so need to download a (potentially) large number of packages to install on this system. Rather than having to through the pain of searching through CRAN to find the packages and all the dependencies and manually download, it would be nice

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Boxplots & Beyond IV: Beanplots

Boxplots & Beyond IV: Beanplots

This post is the last in a series of four on boxplots and some of their extensions.  Previous posts in this series have discussed basic boxplots, modified boxplots based on a robust asymmetry measure, and violin plots, an alternative that essentia...

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Moving from Excel to R

March 5, 2011
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This first post of the Backtesting in Excel and R series will provide some resources to help smooth the transition from the familiarity and comfort of Excel to the potentially strange and intimidating world of R.I made my voyage from Excel to R more th...

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Moving from Excel to R

March 5, 2011
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This first post of the Backtesting in Excel and R series will provide some resources to help smooth the transition from the familiarity and comfort of Excel to the potentially strange and intimidating world of R.I made my voyage from Excel to R more th...

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Choropleths Made Easy!

March 5, 2011
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Choropleths Made Easy!

Choropleth Maps are very useful to visualize spatial trends. There have been several blog posts providing detailed instructions on how to create a choropleth map in R using map, spplot and ggplot2. However, I believe that the p...

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