# Blog Archives

## Careful with tryCatch

June 20, 2016
By

tryCatch is one of the functions that allows the users to handle errors in a simple way. With it, you can do things like: if(error), then(do this). Take the following example: sqrt("a") Error in sqrt("a") : non-numeric argument to mathematical function Now maybe you’d want something to happen when such an error happens. You can achieve that with tryCatch: tryCatch(sqrt("a"), error=function(e) print("You can't take...

## Unit testing with R

March 30, 2016
By

I've been introduced to unit testing while working with colleagues on quite a big project for which we use Python. At first I was a bit skeptical about the need of writing unit tests, but now I must admit that I am seduced by the idea and by the huge time savings it allows. Naturally, I was wondering...

## Bootstrapping standard errors for difference-in-differences estimation with R

November 10, 2015
By

I’m currently working on a paper (with my colleague Vincent Vergnat who is also a Phd candidate at BETA) where I want to estimate the causal impact of the birth of a child on hourly and daily wages as well as yearly worked hours. For this we are using non-parametric difference-in-differences (henceforth DiD) and thus have...

## Update to Introduction to programming econometrics with R

May 2, 2015
By

This semester I taught a course on applied econometrics with the R programming language. For this, I created a document that I gave to my students and shared online. This is the kind of document I would have liked to read when I first started using R. I already had some programming experience in C and Pascal but this...

## Export R output to a file

February 21, 2015
By

Sometimes it is useful to export the output of a long-running R command. For example, you might want to run a time consuming regression just before leaving work on Friday night, but would like to get the output saved inside your Dropbox folder to take a look at the results before going back to work on...

## Introduction to programming econometrics with R

January 11, 2015
By

This semester, I’ll be teaching an introduction to applied econometrics with R, so I’ve decided to write a very small book called “Introduction to programming Econometrics with R”. This is primarily intended for bachelor students and the focus is not much on econometric theory, but more on how to implement econometric theory into computer code, using the R programming...

## R, R with Atlas, R with OpenBLAS and Revolution R Open: which is fastest?

November 10, 2014
By

In this short post, I benchmark different “versions” of R. I compare the execution speeds of R, R linked against OpenBLAS, R linked against ATLAS and Revolution R Open. Revolution R Open is a new open source version of R made by Revolution Analytics. It is linked against MKL and should offer huge speed improvements over...

## Object Oriented Programming with R: An example with a Cournot duopoly

April 23, 2014
By
$P(q) = q^{-\dfrac{1}{\eta}$

I started reading Applied Computational Economics & Finance by Mario J. Miranda and Paul L. Fackler. It is a very interesting book that I recommend to every one of my colleagues. The only issue I have with this book, is that the programming language they use is Matlab, which is proprietary. While there is a free...

## Using R as a Computer Algebra System with Ryacas

December 31, 2013
By

R is used to perform statistical analysis and doesn't focus on symbolic maths. But it is sometimes useful to let the computer derive a function for you (and have the analytic expression of said derivative), but maybe you don't want to leave your comfy R shell. It is possible to turn R into a full-fledged computer...

## Nonlinear Gmm with R – Example with a logistic regression

November 7, 2013
By

In this post, I will explain how you can use the R gmm package to estimate a non-linear model, and more specifically a logit model. For my research, I have to estimate Euler equations using the Generalized Method of Moments. I contacted Pierre Chaussé, the creator of the gmm library for help, since I was having...