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I am happy to announce that my simputation package has appeared on CRAN this weekend. This package aims to simplify missing value imputation. In particular it offers standardized interfaces that make it easy to define both imputation method and imputation … Continue reading → [Read more...]

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A new version of the validate package for data validation was just accepted on CRAN and will be available on all mirrors in a few days. The most important addition is that you can now reference the data set as … Continue reading → [Read more...]

The validate package is our attempt to make checking data against domain knowledge as easy as possible. Here is an example. [crayon-56f5bac53c653388423735/] The summary gives an overview of the number of items checked. For an aggregated test, such as the … Continue reading → [Read more...]

An updated version of the settings package has been accepted on CRAN. The settings package provides alternative options settings management for R. It is aimed to allow for layered options management where global options are the default that can easily … Continue reading → [Read more...]

A new release of stringdist has been accepted on CRAN. stringdist offers a number of popular distance functions between sequences of integers or characters that are independent of character encoding. version 0.9.4 bugfix: edge case for zero-size for lower tridiagonal … Continue reading → [Read more...]

On 24-06-2015 stringdist 0.9.2 was accepted on CRAN. A summary of new features can be found in the NEWS file; here I discuss the changes with some examples. Computing 'dist' objects with 'stringdistmatrix' The R dist object is used as … Continue reading → [Read more...]

The latest release of the stringdist package for approximate text matching has two performance-enhancing novelties. First of all, encoding conversion got a lot faster since this is now done from C rather than from R. Secondly, stringdist now employs multithreading … Continue reading → [Read more...]

Last week I released a new package called settings. It grew out of my frustration built up during several small projects where I'm generating heavily parameterized d3/js output. What I wanted was support to define a whole bunch of option … Continue reading → [Read more...]

An update to the stringdist package was released earlier this month. Thanks to a contribution of Jan van der Laan the package now includes a method to compute soundex codes as defined here. Briefly, soundex encoding aims to translate words … Continue reading → [Read more...]

I came accross this post on SO, where several solutions to sorting data.frames are presented. It must have been solved a million times, but here's a solution I like to use. It benefits from the fact that sort is an … Continue reading → [Read more...]

Recently, Packt published a video course with the above title, and I've just spent a pleasant morning reviewing it on Packt's request. Pleasant, because I think the course gives an excellent introduction to both ggplot2 and shiny. The course is … Continue reading → [Read more...]

After my last post about the stringdist package, Zachary Mayer pointed out to me that the implementation of the Levenshtein and Jaro-Winkler distances implemented in the RecordLinkage package are about two-three times faster. His benchmark compares randomly generated character strings … Continue reading → [Read more...]

I have released a new version of the stringdist package. Besides a some new string distance algorithms it now contains two convenient matching functions: amatch: Equivalent to R's match function but allowing for approximate matching. ain: Similar to R's %in% … Continue reading → [Read more...]

String metrics have important applications in web search, spelling correction and computational biology amongst others. Many different metrics exist, but the most well-known are based on counting the number of basic edit operations it takes to turn one string into … Continue reading → [Read more...]

I've always wondered how exactly the missing value (NA) in R is represented under the hood. Last weekend I was working on a little project that gave me enough excuse to spend some time on finding this out. So, I … Continue reading → [Read more...]

Missing data hinders statistical analyses. Estimating missing values (imputation) prior to analysis is one way to deal with that. In some cases however, the missings need not be estimated at all, since they can be derived with certainty from other … Continue reading → [Read more...]

We (Edwin de Jonge and me) have recently updated our editrules package. The most important new features include (beta) support for categorical data. However, in this post I'm going to show some visualizations we included, made possible by Gabor Csardi's … Continue reading → [Read more...]

update Henrik Bengtsson commented that which(x, arr.ind=TRUE) gives the same result, rendering the blog below academic (thanks for the comment!). So, for academic interest, I'll leave it. In my defense, I implemented this kind of functionality in C some time … Continue reading → [Read more...]