## A Sudoku Puzzle Solver – attempt 1

July 9, 2013
By

I have programmed up a R based Sudoku problem solver for Sudoku puzzles of that only require simple inference.  In these puzzles a solution can be found using only first order inference.  This solver can be found at the end of the code locate...

Read more »

## %in%

July 9, 2013
By

I just stumbled across a really useful infix function in R: %in%. It compares two vectors and returs a logical vector if there is a match or not for its left operand. Let us look at some examples: > 1:10 %in% c(1,3,5,9) TRUE FALSE TRUE...

Read more »

## user2013: The caret tutorial

July 9, 2013
By

This afternoon I went to Max Kuhn’s tutorial on his caret package. caret stands for classification and regression (something beginning with e) trees. It provides a consistent interface to nearly 150 different models in R, in much the same way as the plyr package provides a consistent interface to the apply functions. The basic usage

Read more »

## user2013: The Rcpp tutorial

July 9, 2013
By

I’m at user 2013, and this morning I attended Hadley Wickham and Romain Francois’s tutorial on the Rcpp package for calling C++ code from R. I’ve spent the last eight years avoiding C++ afer having nightmares about obscure pointer bugs, so I went into the room slightly skeptical about this package. I think the most

Read more »

## X+1 uses Revolution R Enterprise for Marketing Optimization

July 9, 2013
By

In a recent article at Statistics View, Lillian Pierson describes how the X+1 Origin Digital Marketing Hub helps companies like JP Morgan Chase and Verizon optimize their marketing efforts. Back in 2011, X+1 saw the need to update their analytics platform to deal with increasing data sizes and to serve the increasingly sophisticated needs of their marketing clients: What...

Read more »

## A Rough Guide to Data Science

July 9, 2013
By

If Big Data was last year's buzzword, Data Science may reach the same level of hype this year. There's no shortage of discussion about the high demand for data scientists, the term's usefulness as a designation, and even declarations of its "sexiness" as a career. And as with many terms that reach a critical mass on social media, data...

Read more »

## For faster R use OpenBLAS instead: better than ATLAS, trivial to switch to on Ubuntu

July 9, 2013
By

R speeds up when the Basic Linear Algebra System (BLAS) it uses is well tuned. The reference BLAS that comes with R and Ubuntu isn't very fast. On my machine, it takes 9 minutes to run a well known R benchmarking script. If I use ATLAS, an optimized BLAS that can be easily installed, the

Read more »

## For faster R use OpenBLAS instead: better than ATLAS, trivial to switch to on Ubuntu

July 9, 2013
By

R speeds up when the Basic Linear Algebra System (BLAS) it uses is well tuned. The reference BLAS that comes with R and Ubuntu isn’t very fast. On my machine, it takes 9 minutes to run a well known R … Continue reading →

Read more »

## Exploratory Data Analysis: Conceptual Foundations of Histograms – Illustrated with New York’s Ozone Pollution Data

Introduction Continuing my recent series on exploratory data analysis (EDA), today’s post focuses on histograms, which are very useful plots for visualizing the distribution of a data set.  I will discuss how histograms are constructed and use histograms to assess the distribution of the “Ozone” data from the built-in “airquality” data set in R.  In

Read more »

## Unicode Tips in Python 2 and R

July 9, 2013
By

Most of time, I don’t need to deal with different encodings at all. When possible, I use ASCII characters. And when there is a little processing in Chinese characters or other Unicode characters, I use .Net languages or JVM languages, in which every string is Unicode and of course when the characters are displayed they are displayed as characters...

Read more »

## googleVis tutorial at useR!2013

July 9, 2013
By

Today Diego and I will give our googleVis tutorial at useR!2013 in Albacete, Spain.googleVis Tutorial at useR! 2013We will cover:Introduction and motivationGoogle Chart ToolsR package googleVisConcepts of googleVisCase studiesgoogleVis on shiny

Read more »

## A possibility for use R and Hadoop together

July 8, 2013
By

(This article was first published on Milano R net, and kindly contributed to R-bloggers) As mentioned in the previous article, a possibility for dealing with some Big Data problems is to integrate R within the Hadoop ecosystem. Therefore, it’s necessary to have a bridge between the two environments. It means that R should be capable of handling data the...

Read more »

## Modeling Residential Electricity Usage with R – Part 2

July 8, 2013
By

(This article was first published on Commodity Stat Arb, and kindly contributed to R-bloggers) I can’t believe it has been nearly 6 months since I last posted.  Given the sustained heat it seemed like a good idea to finish off this subject. As hinted at in my last post, temperature is the missing variable to make sense of Residential...

Read more »

## Another view of ordinary regression

July 8, 2013
By

This is something I’ve been meaning to write for ages. My formal training for most things is limited. Like a lot of folks, I’m an autodidact. This is good in that I’m always learning and always studying those things that I enjoy. At the same time, it means that I take in information in a

Read more »

## Plotting principal component analysis with ggplot #rstats

July 8, 2013
By

This script was almost written on parallel to the sjPlotCorr script because it uses a very similar ggplot-base. However, there’s also a very nice posting over at Martin’s Bio Blog which show alternative approaches on plotting PCAs. Anyway, if you … Weiterlesen →

Read more »

## analyze the american time use survey (atus) with r

July 8, 2013
By

the american time use survey collects information about how we spend our time.  it's a pretty simple setup: sampled individuals write down everything they do for a single twenty-four hour period, in ten minute intervals.  those diaries are a...

Read more »

## Estimating ODE’s parameters

July 7, 2013
By

(This article was first published on Just Another R Blog, and kindly contributed to R-bloggers) To leave a comment for the author, please follow the link and comment on their blog: Just Another R Blog. R-bloggers.com offers daily e-mail updates about R news and tutorials on topics such as: Data science, Big Data, R jobs, visualization (ggplot2, Boxplots, maps,...

Read more »

## change in weight of cars plot

July 7, 2013
By

Based on last week's faster algorithm I wanted to finish with car weights. Unfortunately a fail again. By now it is a fail of myself, it needs a bit more dedication and grunt than I am willing and able to give for this blog. This week I added...

Read more »

## Interactive Heatmaps (and Dendrograms) – A Shiny App

July 7, 2013
By

Heatmaps are a great way to visualize data matrices. Heatmap color and organization can be used to  encode information about the data and metadata to help learn about the data at hand. An example of this could be looking at the raw data  or hierarchically clustering samples and variables based on their similarity or differences.

Read more »

## rgeos: TopologyException – found non-noded intersection between..

July 7, 2013
By

I have been having some issues generating spatial unions and intersections using the rgeos package. The package is extremely powerful, as it serves as an R interface to the powerful GEOS engine. However, when working with shapefiles or polygons, quite often you will come across a whole range of errors, typically around topology exceptions. These occur

Read more »

## ggmap : Interesting toolbox for spatial analysis

July 7, 2013
By

ggmap is a new tool which enables such visualization by combining the spatial information of static maps from Google Maps, OpenStreetMap, Stamen Maps or CloudMade Maps with the layered grammar of graphics implementation of ggplot2The library is developped by David Kahle and Hadley Wickham and in the latest R/Journal (Volume 5/1, June 2013),...

Read more »

## RFM Customer Analysis with R Language

July 7, 2013
By

For database marketing or direct marketing people, they are always concerned about two questions before they send out mails or make calls to their customers:- How can they segment the customers in the database to find out who are more likely to response to their mails or buy their products? Which type of customers they

Read more »

## Variance Swap Replcation in R.

July 6, 2013
By

As I was studying volatility derivatives I made some charts that represent some key features of replication. Say variance swap has a payoff function $$f=(\sigma^2 - K_{VOL})$$, which means that $$K_{VOL}$$ will most likely be the forward volatility cl...

Read more »

## Getting raster histogram in QGIS using SEXTANTE and R

July 6, 2013
By

The issue with the broken histogram creation tool in QGIS annoyed me far too long. Sometimes you just need a quick glance on the histogram of a raster just to make a decision on how to process it or just to assess distribution of classes. But as you kn...

Read more »

## A Recipe for Trellis/Faceted Plots Using Base R Graphics

July 5, 2013
By

I frequently use lattice and ggplot2 to create trellis/faceted graphics. But, I gave up using these packages in a recent application, where I had initially constructed a complex graphic using the base R plotting functions. When I later decided that I wanted a faceted version, there was a dilema: re-create the complex graphic using lattice

Read more »

## Veterinary Epidemiologic Research: Modelling Survival Data – Parametric and Frailty Models

July 5, 2013
By
$Veterinary Epidemiologic Research: Modelling Survival Data – Parametric and Frailty Models$

Last post on modelling survival data from Veterinary Epidemiologic Research: parametric analyses. The Cox proportional hazards model described in the last post make no assumption about the shape of the baseline hazard, which is an advantage if you have no idea about what that shape might be. With a parametric survival model, the survival time

Read more »

## Optimal Pricing for a Simple Monopolist

July 5, 2013
By

# A single price monopolist is a monopolist because it is the only supplier of a particular product. The monopolist therefore has the power to choose a price to sell the product at. # Those who have a willingness to pay which is greater than the ...

Read more »

## Allocation Models With Bounded Dependent Variables

July 5, 2013
By

(This article was first published on Econometrics Beat: Dave Giles' Blog, and kindly contributed to R-bloggers) My post yesterday, on Allocation Models, drew a comment to the effect that in such models the dependent variables take values that must to be non-negative fractions. Well, as I responded, that’s true sometimes (e.g., in the case of market shares); but not in...

Read more »

## Meet the Revolution Analytics UK team

July 5, 2013
By

Revolution Analytics has a new office in London to serve our customers in Europe. This press release introduces the team members who are based there: Neil Miller, Managing Director, International: Neil Miller is responsible for Revolution Analytics' business and growth outside the Americas and is based in the U.K. Neil Miller joined the company after 14 years at Accenture...

Read more »

## Sponsors

Contact us if you wish to help support R-bloggers, and place your banner here.