2447 search results for "gis"

Of Height and Speed in Tennis, or Fuzziness and Techiness in College

April 24, 2011
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Of Height and Speed in Tennis, or Fuzziness and Techiness in College

I thought of this after reading this post and perhaps also this one, one the Cheap Talk blog. Here's the puzzle: in general, being tall does not make you slow; but among professional tennis players, the tall athletes do tend to be relativel...

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Dates in R and the First Day of the Month

April 23, 2011
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Dates in R and the First Day of the Month

I spent some time this morning learning about how R thinks about dates in R. I found this website to be a useful guide.Imagine that your data are dates in a standard format and you want a vector o...

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Dates in R and the First Day of the Month

April 23, 2011
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Dates in R and the First Day of the Month

I spent some time this morning learning about how R thinks about dates in R. I found this website to be a useful guide.Imagine that your data are dates in a standard format and you want a vector o...

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Measuring association using odds ratios

Measuring association using odds ratios

In my last two posts, I have used the UCI mushroom dataset to illustrate two things.  The first was the use of interestingness measures to characterize categorical variables, and the second was the use of binary confidence intervals...

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Common Data Creation Commands

April 19, 2011
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Common Data Creation Commands

Here is a video tutorial where I go through some of the most commonly used commands in creating and manipulating data. As soon as I want to do more than just running a single regression, I use these commands more than any other set of commands (in som...

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Common Data Creation Commands

April 19, 2011
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Common Data Creation Commands

Here is a video tutorial where I go through some of the most commonly used commands in creating and manipulating data. As soon as I want to do more than just running a single regression, I use these commands more than any other set of commands (in som...

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In case you missed it: March Roundup

April 14, 2011
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In case you missed them, here are some articles from February of particular interest to R users. The doSMP package, which enables parallel processing for R on multiprocessor machines, is now available on CRAN. The Offensive Politics blog provided R code used to make a map of precinct returns in the Chicago mayoral election. A connector to integrate R...

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Computing Statistical Power

April 14, 2011
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Computing Statistical Power

Today's task is to compute a statistical power function in R. For a good definition of power, go here. Thinking about the power of a testing procedure is an often-overlooked aspect of hypothesis testing.I also explain what power (in a statistical sens...

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Computing Statistical Power

April 14, 2011
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Computing Statistical Power

Today's task is to compute a statistical power function in R. For a good definition of power, go here. Thinking about the power of a testing procedure is an often-overlooked aspect of hypothesis testing.I also explain what power (in a statistical sens...

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compiler and runiregGibbs (bayesm)

April 13, 2011
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So everyone's excited about the new R 2.13 release because of the compiler package.Apparently it is easy to get a 3x speed increase by simply compiling a function.Doing a lot of the MCMC stuff, I am particularly excited about speed in R. I just compile...

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