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... [Read more...]

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 [Read more...]

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, ... [Read more...]

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 ... [Read more...]

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... [Read more...]

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 ... [Read more...]

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... [Read more...]

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. ... [Read more...]

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 ... [Read more...]

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 ... [Read more...]

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/... [Read more...]

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... [Read more...]

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 ... [Read more...]

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... [Read more...]

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 → [Read more...]

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 ... [Read more...]

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 ... [Read more...]

Regression Through this post I am going to explain How Linear Regression works? Let us start with what is regression and how it works? Regression is widely used for prediction and forecasting in field of machine learning. Focus of regression is on the relationship between dependent and one or more ... [Read more...]

This is something I have had the occasion to do, and never remember how, so this is legitimately a reminder to my future self of how to do things with off-diagonal elements of a matrix. Select rows and columns are easy: mat[1:10, ] or mat[, -c(5)], for... [Read more...]

The Minimum Correlation Algorithm is a heuristic method discovered by David Varadi. Below I will benchmark the execution speed of 2 versions of the Minimum Correlation Algorithm versus the traditional minimum variance optimization that relies on solving a quadratic programming problem. I have run the code above for n=10 (10 assets), n=100 (100 ... [Read more...]