2648 search results for "gis"

The Actuary Puzzle 508 – Square numbers

The Actuary Puzzle 508 – Square numbers

The Actuary Puzzle 508 - Square numbers Author: Matt Malin From the puzzle pages of The Actuary June 2012, I attempt to solve the following, making use of R: This square contains exactly 21 smaller squares. Each of these smaller squares has sides of integer length, with no two smaller squares having sides of the same length. Can you find a solution for...

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The R Journal Volume 4/1, June 2012

July 6, 2012
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As first reported by Paolo, the new R journal is out! You can Download the complete issue from here.  Refereed articles may be downloaded individually using the links below. Table of Contents Editorial 3   Contributed Research Articles   Analysing Seasonal Data  Adrian G Barnett, Peter Baker and Annette J Dobson 5 MARSS: Multivariate Autoregressive State-space...

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Error metrics for multi-class problems in R: beyond Accuracy and Kappa

July 6, 2012
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Error metrics for multi-class problems in R: beyond Accuracy and Kappa

The caret package for R provides a variety of error metrics for regression models and 2-class classification models, but only calculates Accuracy and Kappa for multi-class models.  Therefore, I wrote the following function to allow caret:::train t...

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Fix Overplotting with Colored Contour Lines

July 6, 2012
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Fix Overplotting with Colored Contour Lines

I saw this plot in the supplement of a recent paper comparing microarray results to RNA-seq results. Nothing earth-shattering in the paper - you've probably seen a similar comparison many times before - but I liked how they solved the overplotting...

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More Exploration of Crazy RUT

July 5, 2012
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More Exploration of Crazy RUT

Unintentionally while playing with the lawstat package in R, I started trying to build systems (STANDARD DISCLAIMER: NOT INVESTMENT ADVICE AND WILL LOSE LOTS OF MONEY SO PROCEED WITH CAUTION) based on the Jarque Bera test of normality (entry in Wikiped...

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The Higgs boson: 5-sigma and the concept of p-values

July 4, 2012
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The Higgs boson: 5-sigma and the concept of p-values

Why are physicists talking about 5-sigma, and what's it got to do with statistics? In this short post I'll explain what 5-sigma is and why it's not a measure of how certain scientist are that they've found the Higgs boson

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To the Basics: Bayesian Inference on A Binomial Proportion

July 4, 2012
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To the Basics: Bayesian Inference on A Binomial Proportion

Think of something observable – countable – that you care about with only one outcome or another. It could be the votes cast in a two-way election in your town, or the free throw shots the center on your favorite...

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Graphics Artifacts from Quarterly Commentary

July 2, 2012
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Graphics Artifacts from Quarterly Commentary

For my Q2 2012 commentary, I tried multiple graphs to illustrate the disconnect of the US stock markets with the rest of the world.  I think I finally settled on this simple Excel bar graph populated by Bloomberg data, but I thought some might lik...

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Moving beyond hopeless graphics

July 2, 2012
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I was at a talk awhile ago where the speaker presented tables with 4, 5, 6, even 8 significant digits even though, as is usual, only the first or second digit of each number conveyed any useful information. A graph would be better, but even if you’re too lazy to make a plot, a bit The post Moving...

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Modeling Trick: Masked Variables

July 1, 2012
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Modeling Trick: Masked Variables

A primary problem data scientists face again and again is: how to properly adapt or treat variables so they are best possible components of a regression. Some analysts at this point delegate control to a shape choosing system like neural nets. I feel such a choice gives up far too much statistical rigor, transparency and Related posts:

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