998 search results for "latex"

Describing Data: Frequently Used Commands

May 13, 2011
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Describing Data: Frequently Used Commands

Obtaining a coherent numerical summary of data is a common task, and it is common to want to port these summary statistics into a table of results. When I am in interactive mode with my data, I use the summary() command applied to my data frame. For ...

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Because it’s Friday: French Press Heat Retention

May 13, 2011
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Because it’s Friday: French Press Heat Retention

While responding to this thread on Reddit I made a rough guess as to the heat retention of my french press when completely full of coffee. When I went to bed I realized there was no good reason why I … Continue reading →

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Le Monde puzzle [#14]

May 13, 2011
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Le Monde puzzle [#14]

Last week Le Monde puzzle (I have not received this week issue yet!) was about deriving an optimal strategy in less than 25 steps for finding the 25 answers to a binary multiple choice test, when at each trial, only the number of correct answers is known. Hence, if the correct answers are y1,…,y25, and

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The confusing gamma parameter

May 13, 2011
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The confusing gamma parameter

Boris from Ottawa sent me this email about Introducing Monte Carlo Methods with R: As I went through the exercises and examples, I believe I found a typo in exercise 6.4 on page 176 that is not in the list of typos posted on  your website.  For simulation of Gamma(a,1) random variables with  candidate distribution

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Makefiles and Sweave

May 12, 2011
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Makefiles and Sweave

A Makefile is a simple text file that controls compilation of a target file. The key benefit of using Makefile is that it uses file time stamps to determine if a particular action is needed. In this post we discuss how to use a simple Makefile that compiles a tex file that contains a number

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Extending mtable() to ivreg, gls and robust standard errors

May 9, 2011
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Extending mtable() to ivreg, gls and robust standard errors

I have written several extensions of the mtable() command in the memisc library that may come in handy. The methods are available in a package I have written called tonymisc (now, available on CRAN). A zipped folder with my package files is available...

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Extending mtable() to ivreg, gls and robust standard errors

May 9, 2011
By
Extending mtable() to ivreg, gls and robust standard errors

I have written several extensions of the mtable() command in the memisc library that may come in handy. The methods are available in a package I have written called tonymisc (now, available on CRAN). A zipped folder with my package files is available...

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making meat shares more efficient with R and Symphony

May 9, 2011
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making meat shares more efficient with R and Symphony

In my previous post, I motivated a web application that would allow small-scale sustainable meat producers to sell directly to consumers using a meat share approach, using constrained optimization techniques to maximize utility for everyone involved. In this post, I’ll walk through some R code that I wrote to demonstrate the technique on a small

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What value is cross country GDP correlation? [Part One]

May 6, 2011
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What value is cross country GDP correlation? [Part One]

The above graph borders on chartjunk (and is nothing like Paul Butler’s amazing Facebook map). We can see some variation in color but mostly it is a set of lines between 152 country capitals with no means to determine which … Continue reading →

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Bayesian Confidence Intervals: Obama’s ‘That’-Addition and Informality

May 1, 2011
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Bayesian Confidence Intervals: Obama’s ‘That’-Addition and Informality

No “That” Left Behind? I came across a post on Language Log last week giving some evidence that Obama tends to add that to the prepared version of his speeches. For example, in a recent speech at George Washington University, … Continue reading →

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