1663 search results for "time series"

sab-R-metrics: Brief Sidetrack for Scatterplot Matrices

March 16, 2011
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sab-R-metrics: Brief Sidetrack for Scatterplot Matrices

In my last two posts I talked about Ordinary Least Squares, then extended this discussion to the multiple predictor case and briefly talked about some of the problems that may arise. These problems can include omitted variable bias, heteroskedasticity, non-normality, and multicollinearity. Most of these problems are relatively minor in practice and have easy fixes,...

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sab-R-metrics: Brief Sidetrack for Scatterplot Matrices

March 16, 2011
By
sab-R-metrics: Brief Sidetrack for Scatterplot Matrices

In my last two posts I talked about Ordinary Least Squares, then extended this discussion to the multiple predictor case and briefly talked about some of the problems that may arise. These problems can include omitted variable bias, heteroskedasticity, non-normality, and multicollinearity. Most of these problems are relatively minor in practice and have easy fixes,...

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Using R for Introductory Statistics, The Geometric distribution

March 13, 2011
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Using R for Introductory Statistics, The Geometric distribution

We've already seen two discrete probability distributions, the binomial and the hypergeometric. The binomial distribution describes the number of successes in a series of independent trials with replacement. The hypergeometric distribution describes th...

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Using R for Introductory Statistics, The Geometric distribution

March 13, 2011
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Using R for Introductory Statistics, The Geometric distribution

We've already seen two discrete probability distributions, the binomial and the hypergeometric. The binomial distribution describes the number of successes in a series of independent trials with replacement. The hypergeometric distribution describes the number of successes in a series of independent trials without replacement. Chapter 6 of Using R introduces the geometric distribution - the time to...

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Review: R Graphs Cookbook by Hrishi Mittal

March 11, 2011
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Review: R Graphs Cookbook by Hrishi Mittal

Summary: Very useful for reference while producing graphs, and very comprehensive (including heat-maps, 3D graphs and maps). Reference: Mittal, H. V., 2011, R Graph Cookbook, Packt Publishing, Birmingham, UK, 272 pages,  Publisher’s Website As a scientist I often need to plot graphs of my data, so I am keen to learn more about how to

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My First Few Days with RStudio

March 9, 2011
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My First Few Days with RStudio

As most readers are probably aware, the free IDE for R, called RStudio, was recently released for general use and it immediately made huge waves within the R community. IDE stands for Integrated Development Environment. IDEs typically provides a rich set tools developing in some target language. For standard programming languages like C++ (VisualStudio) and Java (Eclipse or NetBeans),...

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Can one beat a Random Walk– IMPOSSIBLE (you say?)

March 8, 2011
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Can one beat a Random Walk– IMPOSSIBLE (you say?)

Firstly, apologies for the long absence as I've been busy with a few things.  Secondly, apologies for the horrific use of caps in the title (for the grammar monitors).  Certainly, you'll gain something useful from today's musing, as it's a pr...

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In case you missed it: January Roundup

March 8, 2011
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Catching up on roundups today. February roundup will follow soon, but in the meantime enjoy this trip down memory lane - DS. In case you missed them, here are some articles from January of particular interest to R users. Revolution Analytics is now offering annual sponsorship grants for local R user groups worldwide. Issue 2 of the R Journal...

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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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Death Spiral Warning Graph

March 4, 2011
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Death Spiral Warning Graph

In the death spiral scenario, rates go up while the currency goes down.  Here is the way to watch that.  I’m not saying that death spiral of US Dollar and interest rates occurs, but without significant action to restore confidence in fiscal...

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