The new constants package is available on CRAN. This small package provides the CODATA 2014 internationally recommended values of the fundamental physical constants (universal, electromagnetic, physicochemical, atomic…), provided as symbols for direct use within the R language. Optionally, the values with errors and/or the values with units are also provided ... [Read more...]

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In an earlier post I discussed how to avoid overfitting when using Support Vector Machines. This was achieved using cross validation. In cross validation, prediction accuracy is maximized by varying the cost parameter. Importantly, prediction accuracy is... [Read more...]

In an older post, I discussed a number of functions that are useful for programming in R. I wanted to expand on that topic by covering other functions, packages, and tools that are useful. Over the past year, I have been working as an R programmer and these are some ... [Read more...]

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This is the second post in our series on portfolio volatility, variance and standard deviation. If you missed the first post and want to start at the beginning with calculating portfolio volatility, have a look here - Introduction to Volatility. We will use three objects created in that previous post, ... [Read more...]

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The Ecosystems chapter of my Empirical software engineering book has been added to the draft pdf (download here). I don’t seem to be able to get away from rewriting everything, despite working on the software engineering material for many years. Fortunately the sparsity of the data keeps me in ... [Read more...]

I’m extremely pleased to announce that the sergeant package is now on CRAN or will be hitting your local CRAN mirror soon. sergeant provides JDBC, DBI and dplyr/dbplyr interfaces to Apache Drill. I’ve also wrapped a few goodies into the dplyr custom functions that work with Drill ... [Read more...]

The annual useR!2017 conference took place July 4-7 in Brussels, and in every dimension it was the best yet. It was the largest (with over 1,100 R users from around the world in attendance), and yet still very smoothly run with many amazing talks and lots of fun for everyone. If ... [Read more...]

Last month the French elections viewed through Twitter: a semantic analysis post showed how the two contenders were perceived on Twitter during three key events of the campaign (Macron leaks, presidential debate and election day). The goal of the post is to show how to perform this twitter analysis using ... [Read more...]

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This is the fourth part of the series on volatility modelling. For other parts of the series follow the tag volatility. In this exercise set we will explore GARCH-M and E-GARCH models. We will also use these models to generate rolling window forecasts, bootstrap forecasts and perform simulations. Answers to ... [Read more...]

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The latest Spider-man movie, Spider-man: Homecoming, has high hopes for the Marvel Comic Universe just as Wonder woman from the DC universe proved a huge success. The Marvel and DC comic universes both have some great superheros, but only a few of them are succeeding at the box office. I ... [Read more...]

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Table, Org Chart & Tree Map In the seventh part of our series we are going to learn about the features of some interesting types of charts. More specifically we will talk about Table, Org Chart and Tree Map. Read the examples below to understand the logic of what we are ... [Read more...]

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