O gráfico mostra a utilização da hashtag #JeSuisCharlie no twitter no dia 7 de Janeiro de 2015. Tweets vindo principalmente da Europa mas de maneira geral o mundo inteiro estava mostrando solidariedade as vítimas e usando a Hashtag. [Read more...]

[Read more...]

[Read more...]

For Twitter, finding anomalies — sudden spikes or dips — in a time series is important to keep the microblogging service running smoothly. A sudden spike in shared photos may signify an "trending" event, whereas a sudden dip in posts might represent a failure in one of the back-end services that needs ... [Read more...]

[Read more...]

If people do not believe that mathematics is simple, it is only because they do not realize how complicated life is (John von Neumann) I started this blog one year ago and the experience has been better than I could have imagine: Ripples has been viewed about 30.000 times 49 posts published (... [Read more...]

Recursive partitioning is a fundamental tool in data mining. It helps us explore the structure of a set of data, while developing easy to visualize decision rules for predicting a categorical (classification tree) or continuous (regression tree) outcome. Classification and regression trees can be generated through the rpart package. The ... [Read more...]

Or, Retracing my stepsAs I’ve been learning the functionality of Shiny, the web app for R, I have used the helpful tutorials available from the developers at RStudio. At some point, though, one needs to break out and develop one’s own application.  My Shiny app “MLB run scoring ... [Read more...]

[Read more...]

A new release of the RcppCNPy package is now on CRAN. This release mostly solidifies and fixes things. Support for saving integer objects, which was expanded in release 0.2.3, was not entirely correct. Operations on big-endian systems were not up to ... [Read more...]

Fifteen years ago, I initiated a time-honored tradition among my colleagues in kernel development at Sun: shortly after the first of every year, we would get together at our favorite local restaurant to form predictions for the coming year. We made one-year, three-year and six-year predictions for… [Read more...]

It’s a new year, so…new version of RSiteCatalyst on CRAN! For the most part, this release fixes a handful of bugs that weren’t noticed with the prior release 1.4.2 (oops!), but there are pieces of additional functionality. New functionality: Data Feed monitoring For those of you having hourly ... [Read more...]

Cusby Ryan Garner Senior Data Scientist, Revolution Analytics I love creating spatial data visualizations in R. With the ggmap package, I can easily download satellite imagery which serves as a base layer for the data I want to represent. In the code below, I show you how to visualize sampled ... [Read more...]

Recently I was comparing implementation of sequence generation functions in R, Python (numpy) and Julia. Interestingly even such basic functions have slight differences in implementation. In my opinion Julia provides the best solution and Python the wo... [Read more...]

Last week I published a data visualization of San Francisco crime. This week, I’m mapping Seattle crime data. The map above is moderately complicated to create, so I’ll start this tutorial with a simpler case: the dot distribution map. Seattle crime map, simplified version First, we’ll start ... [Read more...]

At the last Cologne R user meeting Holger Zien gave a great introduction to dynamic linear models (dlm). One special case of a dlm is the Kalman filter, which I will discuss in this post in more detail. I kind of used it earlier when I measured the temperature in ... [Read more...]

Motivation Accessing NYT API Extracting and parsing the article body text Writing to MongoDB Pipeline Results Motivation I’ve learned a little about a lot of different corners of the text mining and NLP world over the last few years… which sometimes makes me feel like I know nothing for ... [Read more...]

Right on the heels of yesterday's BH release 1.55.0-2 bringing Boost Fusion, we now have release 1.55.0-3 bringing Boost Graph. To recap, BH is our CRAN package providing (a large part of the) Boost C++ libraries as a set of template headers for use ... [Read more...]

[Read more...]

R has featured packages to support GPU programming for over five years. Beginning with the Gputools package, developers continue to introduce new and more sophisticated tools to take advantage of these powerful coprocessors. The gmatrix package is a recent continuation of this trend which offers some significant new features. Background ... [Read more...]