Merging Dataframes by Partly Matching String

September 29, 2012
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The latest posting by Tony Hirst sparked my attention because I was thinking about a very similar issue recently.I was also fiddling around with agrep and adist until I realised that for this very issue matching of substrings is not as important as matching multiple words.. With this different approach I quite easily matched all but 3...

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Weekend Reading – Gold in October

September 28, 2012
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Weekend Reading – Gold in October

I recently came across the “An early Halloween for gold traders” article by Mark Hulbert. I have discussed this type of seasonality analysis in my presentation at R/Finance this year. It is very easy to run the seasonality analysis using the Systematic Investor Toolbox. This confirms that October have been historically bad for Gold, but

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Browse the in-development R sources at GitHub

September 28, 2012
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As an open-source project, the R source code has always been available to download from the R-project website. You can find source code for the latest released version here, and for the changing-daily new version in progress (R-devel) here. But if you don't have the R sources handy, and just want to check on the contents of a file...

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Second Milano R net meeting

September 28, 2012
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Second Milano R net meeting took place on September, 27. More than thirty R users joining both the presentations session and the open bar. If you attended the meeting, please leave a comment in the page of the meeting. You … Continue reading →

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Photos of the second Milano R net meeting

September 28, 2012
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Photos of the second Milano R net meeting

Photos of the second Milano R net meeting Milano; September 27, 2012

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Optimal seriation for your matrices

September 28, 2012
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Optimal seriation for your matrices

In our previous post, we used a quick-and-dirty method for ordering the axes on our heatmap. It has been pointed out to me that There is a Package for That (which is my nominee for a new slogan for R — not that it needs a slogan). seriation offe...

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Presentations of the second Milano R net meeting

September 28, 2012
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Welcome presentation Andrea Spanò, Partner at Quantide (download PDF, 3.0 MB) Introduction to the next Italian BioR event at PTP Andrea Pedretti, Parco Tecnologico Padano (download PDF, 0.2 MB) Applications of technical risk assessment in Food Industry by R Carlo … Continue reading →

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Reading and Text Mining a PDF-File in R

September 27, 2012
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Reading and Text Mining a PDF-File in R

I just added this R-script that reads a PDF-file to R and does some text mining with it to my Github repo..

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3-D animation of the changing Antarctic ice sheet

September 27, 2012
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Last month we shared an visualization showing the changing extent of Arctic sea-ice. This visualization by the multinational Commission for the Conservation of Antarctic Marine Living Resources (CCAMLR) switches the view to the Southern pole and takes the visualization to a whole new level, by animating it in 3-D: The amount of sea ice in the Southern Ocean surrounding...

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Histogram + Density Plot Combo in R

September 27, 2012
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Histogram + Density Plot Combo in R

Plotting a histogram using hist from the graphics package is pretty straightforward, but what if you want to view the density plot on top of the histogram? This combination of graphics can help us compare the distributions of groups.Let's use...

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Set package repositories at startup

September 27, 2012
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The below code shows how to configure the 'repos' option in R such that install.packages() etc will locate the packages without having to explicitly specify the repository.  Just add it to the .Rprofile file in your home directory (iff missing, create it). For more details, see help("Startup").local({ repos # http://cran.r-project.org/ # For a list of CRAN...

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The simplest Species Distribution Model in OpenBUGS & R

September 27, 2012
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This post demonstrates the simplest Species Distribution Model based on logistic regression for presence/absence data. I heavily simplified the example from Kéry (2010): Introduction to WinBUGS for Ecologists, Chapter 20.Read more →

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ROracle support for TimesTen In-Memory Database

September 27, 2012
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Today's guest post comes from Jason Feldhaus, a Consulting Member of Technical Staff in the TimesTen Database organization at Oracle.  He shares with us a sample session using ROracle with the TimesTen In-Memory database.  Beginning in ve...

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Using R in Political Controversies: Unemployment Reduction Prowess Under Bush versus Obama Years

September 27, 2012
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Using R in Political Controversies: Unemployment Reduction Prowess Under Bush versus Obama Years

Editor’s note: R-bloggers does not take a political side. Since this is an important topic, this post has the comments turned on. Also, If you wish to write a reply post (which includes an R context), you are welcome to contact me to have it published. This post was written by Prof. H. D. Vinod. Fordham University, New York.

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Continuous dispersal on a discrete lattice

September 27, 2012
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Continuous dispersal on a discrete lattice

Dispersal is a key process in many domains, and particularly in ecology. Individuals move in space, and this movement can be modelled as a random process following some kernel. The dispersal kernel is simply a probability distribution describing the distance travelled in a given time frame. Since space is continuous, it is natural to use

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Bounding sums of random variables, part 1

September 27, 2012
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Bounding sums of random variables, part 1

For the last course MAT8886 of this (long) winter session, on copulas (and extremes), we will discuss risk aggregation. The course will be mainly on the problem of bounding  the distribution (or some risk measure, say the Value-at-Risk) for two random variables with given marginal distribution. For instance, we have two Gaussian risks. What could be be worst-case scenario...

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Simplest possible heatmap with ggplot2

September 27, 2012
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Simplest possible heatmap with ggplot2

Featuring the lovely “spectral” palette from Colorbrewer. This really just serves as a reminder of how to do four things I frequently want to do: Make a heatmap of some kind of matrix, often a square correlation matrix Reorder a factor vari...

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Calling Minimum Correlation Algorithm from Excel using RExcel & VBA

September 26, 2012
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Calling Minimum Correlation Algorithm from Excel using RExcel & VBA

I want to show the example of calling the Minimum Correlation Algorithm from Excel. I will use RExcel to connect R and Excel and will create a small VBA cell array function to communicate between Excel and R. I have previously discussed the concept of connecting R and Excel in the “Calling Systematic Investor Toolbox

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eeptools 0.1 Available on CRAN Now!

September 26, 2012
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eeptools 0.1 is available now on CRAN! You can install it by simply typing:install.packages('eeptools')in your R console now. The package allows users to play with a number of built in datasets for folks in education beginning to learn R, custom themes...

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structure and uncertainty, Bristol, Sept. 26

September 26, 2012
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structure and uncertainty, Bristol, Sept. 26

Another day full of interesting and challenging—in the sense they generated new questions for me—talks at the SuSTain workshop. After another (dry and fast) run around the Downs; Leo Held started the talks with one of my favourite topics, namely the theory of g-priors in generalized linear models. He did bring a new perspective on

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Association Rule Learning and the Apriori Algorithm

September 26, 2012
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Association Rule Learning and the Apriori Algorithm

Association Rule Learning (also called Association Rule Mining) is a common technique used to find associations between many variables. It is often used by grocery stores, retailers, and anyone with a large transactional databases. It’s the same way that Target knows your pregnant or when you’re buying an item on Amazon.com they know what else you want

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Merging Data Sets Based on Partially Matched Data Elements

September 26, 2012
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Merging Data Sets Based on Partially Matched Data Elements

A tweet from @coneee yesterday about merging two datasets using columns of data that don’t quite match got me wondering about a possible R recipe for handling partial matching. The data in question related to country names in a datafile that needed fusing with country names in a listing of ISO country codes. The original

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R courses in Belgium

R courses in Belgium

Every year, the Leuven Statistics Research Center (Belgium) is offering short courses for professionals and researchers in statistics and statistical tools. The following link shows the overview of the courses: http://lstat.kuleuven.be/consulting/shortcourses/ENcourse%20overview.htm or get it here in pdf: http://lstat.kuleuven.be/consulting/shortcourses/BRO_LSTAT_2012-2013.pdf This year, BNOSAC is presenting the course on Advanced R Programming Topics, which will be held on Oktober 18-19. This course...

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Creating Scientific Posters using R, Latex, Beamer and Beamerposter

September 26, 2012
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Creating Scientific Posters using R, Latex, Beamer and Beamerposter

A while ago I had the need to produce some posters that included lots of data (scientific style).  Having recently got back into R and learning LaTex I googled for a way to do this using R.  Here's what I found and ended up with, using R, LaT...

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Using R in production: industry experts share their experiences

September 26, 2012
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I had a great time yesterday moderating the "R in Action" panel discussion at the DataWeek conference in San Francisco. Each of the panelists represented a company that is actively using R and/or Revolution R Enterprise. Here (from memory, since I couldn't take notes) are some the things they shared: Jesse Bridgewater from eBay talked about how R is...

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R Studio and Revolution R impressions

September 26, 2012
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R Studio and Revolution R impressions

I have used R for about six years now. Over the years I’ve done the majority of my coding in Linux and so R has been nothing more than a terminal. I enjoy the simplicity and purity of the terminal but...

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Some regressions on school data

September 26, 2012
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Some regressions on school data

Eric and I have been exchanging emails about potential analyses for the school data and he published a first draft model in Offsetting Behaviour. I have kept on doing mostly data exploration while we get a definitive full dataset, and … Continue reading →

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rasterVis to the rescue

September 26, 2012
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rasterVis to the rescue

Programmers like Oscar Perpiñán Lamigueiro are the reason I love R!  Oscar is the maintainer of the rasterVis package and it in this post I’ll explain why it is must have package for anyone working with the raster package in R.  My latest project is focused on the NOAA’s Climate Reference Network. The details can

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Predict Bounce Rate based on Page Load Time in Google Analytics

September 26, 2012
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Predict Bounce Rate based on Page Load Time in Google Analytics

Welcome to the second part. In the last blog post on Linear Regression with R, we have discussed about what is regression? and how it is used ? Now we will apply that learning on a specific problem of prediction. In this post, I will create a basic model to predict bounce rate as function

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