Monthly Archives: April 2012

Eclipse + Rcpp + RInside = Magic

April 8, 2012
By
Eclipse + Rcpp + RInside = Magic

  I've been doing R/Java development for some time, creating packages both large and small with this tool chain. I have used Eclipse as my package development environment almost exclusively, but I didn't realize how much I relied on the IDE before I had to do some serious R/C++ package development. My first Rcpp package (wordcloud)

Read more »

Sampling and the Analysis of Big Data

April 8, 2012
By
Sampling and the Analysis of Big Data

After my last post, I came across a few articles supporting the opinion that if you have a good reason to take random samples from a “big” dataset, you’re not committing some kind of sin: Big Data Blasphemy: Why Sample? … Continue reading →

Read more »

The lm() function with categorical predictors

April 8, 2012
By
The lm() function with categorical predictors

What's with those estimates?By Ben OgorekIn R, categorical variables can be added to a regression using the lm() function without a hint of extra work. But have you ever look at the resulting estimates and wondered exactly what they were?First, let's define a data set.set.seed(12255)n = 30sigma = 2.0AOV.df <- data.frame(category = c(rep("category1", n)     ...

Read more »

Small pedigree based mixed model example

April 8, 2012
By

Pedigree based mixed models (often called animal models, due to modelling animal performance) are the cornerstone of animal breeding and quantitative genetics. There are many programs that can be used for analyzing your data with these models, e.g., ASREML, BLUPf90, MATVEC, MiXBLUP & MiX99,  SurvivalKit, PEST/VCE, WOMBAT, ...). There are also R packages you...

Read more »

Sorting the "Sample Sets" by constituents

April 8, 2012
By
Sorting the "Sample Sets" by constituents

I use to see the videos from:http://www.twotorials.com/and the video:How to order and sort stuff in Ris really useful to apply this concept to organize and understand better our sample sets before to proceed to develop a calibration.The idea of this po...

Read more »

Predicting apple liking from instrumental data

April 8, 2012
By
Predicting apple liking from instrumental data

In this post I will examine if the individual models from previous posts together would make a good predictive model. Obviously, predictive capability is different from descriptive capability, predictions usually have a more simple model. As there was ...

Read more »

Course: Analysing Palaeolimnological Data with R

April 8, 2012
By
Course: Analysing Palaeolimnological Data with R

Update: As of 18 April 2012 the course is now fully subscribed. Should you wish to be placed on a waiting list please contact Steve Juggins. Analysing Palaeolimnological Data with R 16th — 20th August 2012, University Marine Biological Station … Continue reading →

Read more »

Course: Analysing Palaeolimnological Data with R

April 8, 2012
By

16th — 20th August 2012, University Marine Biological Station Millport, Isle of Cumbrae, Scotland. Steve Juggins and I will be running a 4-day residential R course to coincide with the International Paleolimnology Symposium 2012 this August. The course will be held at the University Marine Biological Station Millport on the Isle of Cumbrae, within easy...

Read more »

Using bigmemory for a distance matrix

April 7, 2012
By
Using bigmemory for a distance matrix

The process of working on metadata and temperature series gives rise to several situations where I need to calculate the distance from every station to every other station. With a small number of stations this can be done easily on the fly with the result stored in a matrix. The matrix has rows and columns

Read more »

Newton’s Method In R

Here is a toy example of implementing Newton’s method in R. I found some old code that I had written a few years ago when illustrating the difference between convergence properties of various root-finding algorithms, and this example shows a … Continue reading →

Read more »