April 2012

When R met SAP Gateway

April 20, 2012 | Alvaro "Blag" Tejada Galindo

A couple of days ago, I was toying with the idea of doing something with SAP Gateway...I thought of using SUP, but as I recently wrote 2 blogs about it, I decided to go back to one of my favorite programming languages...R...So...Gateway can be consumed... [Read more...]

Generating all subsets of a set

April 20, 2012 | Bogumił Kamiński

Recently I have calculated Banzhaf power index. I required generation of all subsets of a given set. The code given there was a bit complex and I have decided to write a simple function calculating it. As an example of its application I reproduce Figur...
[Read more...]

PhD week 7: Plotting and NIR spectroscopy

April 19, 2012 | Samuel Brown

Near-infrared (NIR) spectroscopy is a technique that measures the amount of heat absorbed or emitted by certain materials. It is used in a variety of applications, but in the agricultural world, it is often used to determine the quality and composition of mixed materials such as stock forage. It uses ... [Read more...]

Simple tools for building a recommendation engine

April 19, 2012 | Joseph Rickert

By Joseph Rickert Revolution’s resident economist, Saar Golde, is very fond of saying that “90% of what you might from a recommendation engine can be achieved with simple techniques”. To illustrate this point (without doing a lot of work), we downloaded the million row movie dataset from www.grouplens.org ... [Read more...]

Tutorial: Using plot() function

April 19, 2012 | alstated

Hello Readers! This is my first post as a member ofR-bloggers. In this post I'm going to talk about the basic plotting in R, fortwo dimensional. This is a tutorial for beginners in R.To begin with, let's define a vector first. Say wehave vector x, whic...
[Read more...]

Dummies for Dummies

April 19, 2012 | diffuseprior

Most R functions used in econometrics convert factor variables into a set of dummy/binary variables automatically. This is useful when estimating a linear model, saving the user from the laborious activity of manually including the dummy variables as regressors. However, what if you want to reshape your dataframe so ... [Read more...]

Matrix vs Data Frame in R

April 19, 2012 | civilstat

Today I ran into a double question that might be relevant to other R users: Why can’t I assign a dataframe row into a matrix row? And why won’t my function accept this dataframe row as an input argument? A … Continue reading → [Read more...]

User Input in R vs Python

April 18, 2012 | Abraham Mathew

Both R and Python have facilities where the coder can write a script which requests a user to input some information. In Python 2.6, the main function for this task is raw_input (in Python 3.0, it’s input()). In R, there are a series of functions that can be used to ... [Read more...]

Efficient Frontier of Funds and Allocation Systems

April 18, 2012 | klr

I did a very basic experiment in Efficient Frontier of Buy-Hold and Tactical System where I determined the efficient frontier of the S&P 500 with itself transformed by a Mebane Faber 10-month moving average tactical allocation. The result was inter...
[Read more...]

Visualizing iOS Text Editors

April 18, 2012 | Kieran Healy

The other day Brett Terpstra posted a gigantic and quite beautifully-executed feature comparison of all of the text editors available for iOS devices. The table is really terrific and also a bit overwhelming, as there's so much data. On the bus home ye... [Read more...]

knitr Performance Report-Attempt 2

April 18, 2012 | klr

Over the years I have changed my learning process from reading thoroughly first before proceeding to reading minimally and then applying immediately.  I very quickly see the gaps in my knowledge.  This method is far more painful but seems to ...
[Read more...]
1 4 5 6 7 8 15

Never miss an update!
Subscribe to R-bloggers to receive
e-mails with the latest R posts.
(You will not see this message again.)

Click here to close (This popup will not appear again)