2608 search results for "GIS"

The Joy of R: A Feline Guide

November 5, 2011
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The Joy of R: A Feline Guide

Just because it’s caturday Images by Mario Pineda-Krch (CC BY-NC-SA 3.0) This is from the “Mario’s Entangled Bank” blog ( http://pineda-krch.com ) of Mario Pineda-Krch, a theoretical biologist at the University of Alberta. Filed under: cats, computing, humour, R, Sweave

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Webinar on Portfolio Rebalancing with R and Sybase

November 3, 2011
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R users in the financial industry may be interested in the following webinar hosted by Revolution Analytics' partner Sybase on November 10: Portfolio Rebalancing Using R and Sybase RAP for Intraday Risk Management With volatility and violent intraday swings becoming the new normal, intraday risk controls are now needed to not only reduce your exposures across multiple asset classes,...

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Please use sensible colours in your maps

November 2, 2011
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If you are creating maps then for goodness sake Use sensible colours!  I was helping some undergraduates with some work the other day, and they decided to use the following colour scheme for representing river depth: Deep water: Red Medium-depth water: Bright green Shallow water: Pink Why did they do this? Well, either they were

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Cycles in finite populations: A reproducible seminar in three acts

November 1, 2011
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Cycles in finite populations: A reproducible seminar in three acts

For this years Halloween I presented the mathematical biology seminar at the Centre for Mathematical Biology. Here is the title and the abstract… Cycles in finite populations: a reproducible seminar in three acts Many natural populations exhibit cyclic fluctuations. Explaining the underlying … Continue reading →

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Use case: combining taxize and rgbif

November 1, 2011
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Use case: combining taxize and rgbif

Sure thing….this is just the sort of thing for which rOpenSci is being built. A colleague of mine recently saw our packages in development and thought, “Hey, that could totally make my life easier.”   What was made easier you ask?   This was his situation: He had a list of ca. 1200 species of

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How Might Data Journalists Show Their Working? Sweave

November 1, 2011
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How Might Data Journalists Show Their Working? Sweave

If part of the role of data journalism is to make transparent the justification behind claims that are, or aren’t, backed up by data, there’s good reason to suppose that the journalists should be able to back up their own data-based claims with evidence about how they made use of the data. Posting links to

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Using Sparse Matrices in R

October 31, 2011
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Using Sparse Matrices in R

Introduction I’ve recently been working with a couple of large, extremely sparse data sets in R. This has pushed me to spend some time trying to master the CRAN packages that support sparse matrices. This post describes three of them: the Matrix, slam and glmnet packages. The first two packages provide data storage classes for

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Plotting grouped data vs time with error bars in R

October 31, 2011
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Plotting grouped data vs time with error bars in R

This is my first blog since joiningR-bloggers. I’m quite excited to be part of this group and apologize if I boreany experienced R users with my basic blogs for learning R or offendprogrammers with my inefficient, sloppy coding. Hopefully writing for...

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Risk parity

October 31, 2011
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Risk parity

Some thoughts and resources regarding a popular fund management buzzword. The idea Given asset categories (like stocks, bonds and commodities) create a portfolio where each category contributes equally to the portfolio variance. Two operations There are two cases in creating a risk parity portfolio: the universe is the asset categories the universe is the assets … Continue reading...

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Modelling with R: part 5

October 30, 2011
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In our exercise of learning modelling in R, we have till now succeeded in doing the following:Importing the dataPreparing and transforming the dataRunning a logistic regressionCreating a decision treeSpecifically, we created a decision tree using the r...

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