2809 search results for "GIS"

Quantitative palaeolimnology: my book chapters are finally out!

April 23, 2012
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Quantitative palaeolimnology: my book chapters are finally out!

Today I received confirmation that the delayed fifth volume in the Developments in Palaeoenvironmental Research series has been published. The book is titled Data Handling and Numerical methods, though it covers more of the latter and, IMHO, is far more interesting than … Continue reading →

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Probit/Logit Marginal Effects in R

April 23, 2012
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Probit/Logit Marginal Effects in R

The common approach to estimating a binary dependent variable regression model is to use either the logit or probit model. Both are forms of generalized linear models (GLMs), which can be seen as modified linear regressions that allow the dependent variable to originate from non-normal distributions. The coefficients in a linear regression model are marginal

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Visualising the Path of a Genetic Algorithm

April 23, 2012
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Visualising the Path of a Genetic Algorithm

We quite regularly use genetic algorithms to optimise over the ad-hoc functions we develop when trying to solve problems in applied mathematics. However it’s a bit disconcerting to have your algorithm roam through a high dimensional solution space while not being able to picture what it’s doing or how close one solution is to another. … Continue reading...

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Quantitative palaeolimnology: my book chapters are finally out!

April 23, 2012
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Quantitative palaeolimnology: my book chapters are finally out!

Today I received confirmation that the delayed fifth volume in the Developments in Palaeoenvironmental Research series has been published. The book is titled Data Handling and Numerical methods, though it covers more of the latter and, IMHO, is far more interesting than the dry title would suggest (who gets excited by Data Handling? Well, one or two people perhaps...

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118 years of US State Weather Data

April 22, 2012
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118 years of US State Weather Data

A recent post on the Junkcharts blog looked at US weather dataand the importance of explaining scales (which in this case went up to 118). Ultimately, it turns out that 118 is the rank of the data compared to the previous 117 years of data (in ascending order, so that 118 is the highest). At … Continue reading...

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Most profitable hedge fund style

April 21, 2012
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Most profitable hedge fund style

This is not an investment advice!! Couple of weeks back, during amst-R-dam user group talk on backtesting trading strategies using R, I mentioned the most effective style for hedge funds is relative value statistical arbitrage, I read it somewhere. After … Continue reading →

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Revolution Newsletter: April 2012

April 20, 2012
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The most recent edition of the Revolution Newsletter is out. The news section is below, and you can read the full April edition (with highlights from this blog and community events) online. You can subscribe to the Revolution Newsletter to get it monthly via email. Spring Webinar Series. Our Spring Webinar Series features presentations from Revolution Analytics staff and...

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Getting Historical Weather Data in R and SAP HANA

April 19, 2012
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For many of my latest data blogs, I needed historical weather data to perform data mash-ups to pin-point the cause.  For example, for my continued exploration into the airlines/airports historical data using SAP HANA and R, I wanted to find out wh...

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An R Script to Automatically download PubMed Citation Counts By Year of Publication

April 19, 2012
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An R Script to Automatically download PubMed Citation Counts By Year of Publication

Ever wanted to look at PubMed trends and make elegant graphs of them? Here’s an R script that will do it automatically for you.

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Tutorial: Using plot() function

April 19, 2012
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Tutorial: Using plot() function

Hello Readers! This is my first post as a member ofR-bloggers. In this post I'm going to talk about the basic plotting in R, fortwo dimensional. This is a tutorial for beginners in R.To begin with, let's define a vector first. Say wehave vector x, whic...

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