Category Archives: R Language

The Logit Function

Posted on August 29, 2016 by jamesdmccaffrey

My background is in mathematics. One thing about math that I find simultaneously fascinating and confusing is that there are an insane number of conceptual connections between different ideas. Fully understanding connections takes months or years of study. An example … Continue reading →

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Another Look at R Tools for Visual Studio

Posted on August 26, 2016 by jamesdmccaffrey

Microsoft is making big investments in the R language. R is used mostly for data analyses, for example, performing a linear regression analysis on some data. The basic R language is very old. When you install Base R, you get … Continue reading →

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R Language Basic Data Structures

Posted on August 11, 2016 by jamesdmccaffrey

I wrote an article titled “R Language Basic Data Structures” in the August 2016 issues of Visual Studio Magazine. See https://visualstudiomagazine.com/articles/2016/08/01/r-language-basic-data-structures.aspx. I program in several different languages. Whenever I’m learning a new language, one of the first thing I want … Continue reading →

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Permutations using R

Posted on July 18, 2016 by jamesdmccaffrey

I wrote an article in the July 2016 issue of MSDN Magazine titled “Permutations using R”. See https://visualstudiomagazine.com/articles/2016/07/01/permutations-using-r.aspx. A mathematical permutation of order n is one possible arrangement of n items. In R the items are the integers 1 through … Continue reading →

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Estimating Binomial Probabilities using the Normal Approximation and C#

Posted on July 16, 2016 by jamesdmccaffrey

Suppose you flip a coin 10 times. What is the probability you’ll get exactly 2 heads? This is an example of a binomial probability problem. In math terms n is the number of trials (10 for the example), k is … Continue reading →

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R Tools for Visual Studio

Posted on July 7, 2016 by jamesdmccaffrey

I’ve been keeping an eye on the progress of the R Tools for Visual Studio (RTVS) project. RTVS is an add-in for the Visual Studio program. A preview version of RTVS was announced in March 2016. See https://blogs.msdn.microsoft.com/visualstudio/2016/03/22/introducing-r-tools-for-visual-studio-3/. It’s too … Continue reading →

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The R Language nnet Package

Posted on June 24, 2016 by jamesdmccaffrey

The R language has many hundreds (at least — probably thousands) of functions that can perform classical statistics tests and analyses. The R language also has functions that can perform machine learning tasks. The nnet (neural network) package used to … Continue reading →

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How the R Language Does OOP

Posted on June 21, 2016 by jamesdmccaffrey

I wrote an article titled “How the R Language Does OOP” in the June 2016 issue of Visual Studio Magazine. See https://visualstudiomagazine.com/articles/2016/06/01/how-the-r-language-does-oop.aspx. The R language is most often used by data scientists and developers in an interactive mode. But you … Continue reading →

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Calculating the Area under the Normal Distribution using C#

Posted on June 18, 2016 by jamesdmccaffrey

Every now and then, just for fun, I like to code up a standard statistical test using C#. When doing so, it’s fairly common to need to programmatically calculate the area under the Normal (aka Gaussian, aka bell-shaped) distribution. I … Continue reading →

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R Language Generating Random Integers

Posted on June 11, 2016 by jamesdmccaffrey

Generating random numbers is a fundamental task in many kinds of programming. I decided to investigate how to generate random integers using the R language. I came up with three techniques. My conclusion is that using the built-in sample() function … Continue reading →

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