4481 search results for "git"

Time Varying Higher Moments with the racd package.

April 22, 2013
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Time Varying Higher Moments with the racd package.

The Autoregressive Conditional Density (ACD) model of Hansen (1994) extended GARCH models to include time variation in the higher moment parameters. It was a somewhat natural extension to the premise of time variation in the conditional mean and variance, though it probably raised more questions than it, or subsequent research have been able to answer.

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R et Twitter

April 22, 2013
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R et Twitter

(This article was first published on Learning Data Science , and kindly contributed to R-bloggers) On va dans ce post, illustrer une utilisation simple des packages twitteR, StreamR, tm qui permettent faire du textmining. En réalité, les deux premiers permettent de récuperer les tweets et de faire des comptages simples et complexes et le dernier permet de faire du...

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2D plot with histograms for each dimension (2013 edition)

April 22, 2013
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2D plot with histograms for each dimension (2013 edition)

In 2009, I wrote about a way to show density plots along both dimensions of a plot. When I ran the code again to adapt it to a new project, it didn't work because ggplot2 has become better in the meantime. Below is the updated code. Using the gridExtra...

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Using data.table for binning

Using data.table for binning

I discovered the impressive data.table package more than a year ago. In order to learn how to use it, I …Continuar leyendo »

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analyze the medical large claims experience study (mlces) with r

April 21, 2013
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not a survey, not even remotely current, the society of actuaries' medical large claims experience study (mlces) might be the best private health insurance claims data available to the public.  this data should be used to calibrate other data sets...

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What Is the Probability of a 16 Seed Beating a 1 Seed?

April 21, 2013
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What Is the Probability of a 16 Seed Beating a 1 Seed?

Note: I started this post way back when the NCAA men's basketball tournament was going on, but didn't finish it until now. Since the NCAA Men's Basketball Tournament has moved to 64 teams, a 16 seed as never upset a 1 seed. You might be tempted to say ...

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Ordinal data, models with observers

April 21, 2013
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I recently made three posts regarding analysis of ordinal data. A post looking at all methods I could find in R, a post with an additional method and a post using JAGS. Common in all three was using the cheese data, a data set where...

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What Is the Probability of a 16 Seed Beating a 1 Seed?

April 20, 2013
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What Is the Probability of a 16 Seed Beating a 1 Seed?

Note: I started this post way back when the NCAA men's basketball tournament was going on, but didn't finish it until now. Since the NCAA Men's Basketball Tournament has moved to 64 teams, a 16 seed as never upset a 1 seed. You might be tempted to say...

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Modeling habitat diversity and species richness

April 20, 2013
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Modeling habitat diversity and species richness

How does habitat diversity affect species richness? Perhaps intuition suggests that habitat diversity increases species richness by facilitating niche or resource partitioning among species. But, for a fixed area, as habitat heterogeneity increases, the area that can be allocated to each habitat type decreases. In a recent paper, Allouche and colleagues (2012) provide a theoretical and empirical treatment...

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Agent-based modeling in R – habitat diversity and species richness

April 20, 2013
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Agent-based modeling in R – habitat diversity and species richness

How does habitat diversity affect species richness? Perhaps intuition suggests that habitat diversity increases species richness by facilitating niche or resource partitioning among species. But, for a fixed area, as habitat heterogeneity increases, the area that can be allocated to each habitat type decreases. In a recent paper, Allouche and colleagues (2012) provide a theoretical and empirical treatment...

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