334 search results for "boxplot"

Maps of solar radiation

Maps of solar radiation

The Atmospheric Science Data Center (ASDC) at NASA Langley Research Center offers several data sources. For example, it is possible to download a text file with the 22-year (July 1983 – June 2005) monthly and annual average of global horizontal irradiation. nasafile <- 'http://eosweb.larc.nasa.gov/sse/global/text/global_radiation' nasa <- read.table(file=nasafile, skip=13, header=TRUE) With this data, R and the

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Bond Market as a Casino Game Part 1

April 1, 2011
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Bond Market as a Casino Game Part 1

With this post, I am doing something I try very hard to avoid, especially when communicating to my clients, and that is blurring the line between investing and gambling.  But after reading all of Reuven Brenner’s books and finishing Ralph Vince ...

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Baseball, T-tests and statistical surprises

March 31, 2011
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Baseball, T-tests and statistical surprises

Are MLB players better hitters now than they were 20 years ago? Revolution Analytics' Joseph Rickert uses R to take a look at the data, and offers an instructive lesson in checking your assumptions for statistical tests in the process -- Ed. Data are everywhere – but, even for simple things, I still seem to spend a too much...

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The Many Uses of Q-Q Plots

The Many Uses of Q-Q Plots

My last four posts have dealt with boxplots and some useful variations on that theme.  Just after I finished the series, Tal Galili, who maintains the R-bloggers website, pointed me to a variant I hadn’t seen before.  It's called a bee...

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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
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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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Using R for Introductory Statistics, Chapter 5, Probability Distributions

February 9, 2011
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Using R for Introductory Statistics, Chapter 5, Probability Distributions

In Chapter 5 of Using R for Introductory Statistics we get a brief introduction to probability and, as part of that, a few common probability distributions. Specifically, the normal, binomial, exponential and lognormal distributions make an appearance....

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Using R for Introductory Statistics, Chapter 5, Probability Distributions

February 9, 2011
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Using R for Introductory Statistics, Chapter 5, Probability Distributions

In Chapter 5 of Using R for Introductory Statistics we get a brief introduction to probability and, as part of that, a few common probability distributions. Specifically, the normal, binomial, exponential and lognormal distributions make an appearance. For each distribution, R provides four functions whose names start with the letters d, p, q or r followed by...

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Clustering NHL Skaters

February 6, 2011
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Clustering NHL Skaters

I have been sitting on this post for some time now and wanted to get it out there.  The goal is to simply show how easy it is to pull live data from the web into R, massage it, and perform some analytics on it.  I am not sure how useful this analysis really is

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sab-R-metrics: Intermediate Scatter Plots

January 25, 2011
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sab-R-metrics: Intermediate Scatter Plots

First off, I'll say it's been a whirlwind of a past few days. Thanks to David Smith at the Revolutions Blog for his kind words about the sab-R-metrics series and link back this way. Add in Ed Kupfer's posts at the APBRmetrics board, Harry Pavlidis at THT, Dave Allen at Fangraphs...

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