2615 search results for "GIS"

Peer-reviewed R packages?

November 22, 2012
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Peer-reviewed R packages?

Dear R-Users, a question: I am the author of the ‘qpcR’ package. Within this, there is a function ‘propagate’ that does error propagation based on Monte Carlo Simulation, permutation-based confidence intervals and Taylor expansion. For the latter I recently implemented a second-order Taylor expansion term that can correct for nonlinearity. The formulas are quite complex

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We NEED more data

November 22, 2012
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We NEED more data

Email One of the historic difficulties of doing research on urban energy systems has been the limited availability of data at sufficiently detailed spatial resolutions. Without this data, you might end up relying on aggregate information about the built environment, building occupants, and local geography that doesn't apply to the specifics of a particular neighbourhood

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Connecting R to an Oracle database with RJDBC

November 22, 2012
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In many circumstances, you might want to connect R directly to a database to store and retrieve data.  If the source database is an Oracle database, you have a number of options: ROracle RODBC RJDBC   Using ROracle should theoretically… Read more ›

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Happy Thanksgiving from is.R()!

November 22, 2012
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Happy Thanksgiving from is.R()!

Today’s post is mostly to wish everyone a Happy Thanksgiving. We will be taking the rest of the week off, and will return on Monday. Below is some code to reproduce the adorable Turkey above; enjoy! https://gist.github.com/4122464

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Upcoming Webinar: Real-time, big-data analytics

November 21, 2012
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A quick heads-up that I'll be presenting another brand-new webinar on Thursday next week (November 29). In Real-time Big Data Analytics: From Deployment to Production, I'll review the process of making predictive models work in real-live operational environments. I'll also tackle those ubiquitous buzz-words "real-time" and "big data", and the fact that they can mean very different things in...

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IPython vs RStudio+knitr

November 21, 2012
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IPython vs RStudio+knitr

At a meeting last night with some collaborators at the Vélobstacles project, I was excitedly told about the magic of IPython and it’s notebook functionality for reproducible research. This sounds familiar, I thought to myself. Using a literate programming approach to integrate computation with the communication of methodology and results has been at the core

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Representing density in two dimensions

November 21, 2012
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Representing density in two dimensions

I’ll be subbing today for Chris, as we continue to explore some ggplot2 basics. Today, imagine that you have data distributed in two dimensions, and that you would like to convey differences in point density over space. As with many things, this...

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Upcoming events

November 20, 2012
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Upcoming events

New Events  Thalesians (London) 2012 November 21: Isabel Ehrlich on “Basket Options with Smile”. Abstract: Due to the distinct lack of models for basket options that remain consistent with the market smile we look at approximations that are able to accurately replicate the volatility smile. Notably we turn to the use of an Edgeworth series … Continue reading...

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Prime Factorization Visualization with R and Shiny

November 20, 2012
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Prime Factorization Visualization with R and Shiny

Quite a lot of people have had fun recently with prime factorization. It all started on The Math Less Traveled, then various versions of the prime factorization diagrams appeared (here, here, this animated one, etc., they are actually more or less listed here). So I wanted to have fun too and give a try...

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Drawdown Determined Position Size

November 19, 2012
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Drawdown Determined Position Size

This caught my eye as I searched for some more academic research on my favorite risk measure drawdown. Yang, Z. George and Zhong, Liang,Optimal Portfolio Strategy to Control Maximum Drawdown - The Case of Risk Based Dynamic Asset Allocation (February ...

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