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Finally after learning a couple of weeks ago, about the new support for HTTPS backed by the "Let's Encrypt" offered by Dreamhost, I decided to use it on my main site.

So far, everything seems just fine, and I am happy that is working.

Note from 2016-06-10: After a few minor issues, at the beginning, the automatic renovation of the certificates is now running smoothly, it is a testament to the high quality support by Dreamhost.

Introduction

For the "Practical Machine Learning" course at Coursera, the class was given a dataset from a Human Activity Recognition (HAR) study¹ that tries to assess the quality of an activity (defined as “... the adherence of the execution of an activity to its specification ...”), namely a weight lifting exercise, using data from sensors attached to the individuals and their equipment.

Background

Sitepoint has published the results of their 2015 PHP Framework popularity survey¹. In that post they show that the survey gives a very large edge to Laravel. The people at Sitepoint were also nice enought to publish their properly anonymized dataset in a github repo²

So I went ahead, and forked their repo and fired up R to give this data a go.

Background

Motivation

I am currently reading the book "Machine Learning with R"¹ by Brent Lantz, and also want to learn more about the caret² package, so I decided to replicate the SPAM/HAM classification example from the chapter 4 of the book using caret instead of the e1071³ package used in the text.

There are other differences apart from using a different R package: instead of using as comparison the number of false positives, I decided to use the sensitivity and specificity as criteria to evaluate the prediction models. Also, I used the calculated models on a (different) second dataset to test their validity and prediction performance.

Background

Motivation

I am currently reading the book "Machine Learning with R"¹ by Brent Lantz, and also want to learn more about the caret² package, so I decided to replicate the kNN example from the chapter 3 of the book using caret instead of the class³ package used in the text.

It seems that there is a bit of a problem with using Mathjax and Cloudflare, for some reason the math does not render at all, even when using the Mathjax from cdnjs (Cloudflare's own CDN).

(Kai at ~3 weeks)

On 2014-09-25 at 00:06h (PET) our second son Kai (魁) was born, after about 5 hours of labor.

Este es un ejemplo nada elaborado del uso del servicio de datos abiertos disponibles por parte del municipio de Lima Metropolitana, en el cual ponemos en un mapa los paraderos de corredor TGA (Tacna-Garcilazo-Armedáriz) en un par de formas distintas.

El servicio en cuestión usa Junar como plataforma. Existen librerías para varios lenguajes de programación, pero no para R; pero felizmente el API es basado en REST y la respuesta de las llamadas es un arreglo en JSON, de manera que es factible consumir los datos usando la librería jsonlite.

Project for the "Statistical Inference" course (Coursera, Aug. 2014)

Compare simulated mean and variace with the theoretical values

We will run 1000 rounds of simulation of 40 exponentials with \lambda = 0.2, using a fixed seed, and comparing the center of the distribution of the mean and variance values with the theoretical 1 / \lambda: