2799 search results for "twitteR"

Benford’s Law

April 16, 2012
By
Benford’s Law

Here is a quick quiz. If you visit the Wikipedia page List of countries by GDP, you will find three lists ranking the countries of the world in terms of their Gross Domestic Product (GDP), each list corresponding to a different source of the data. If you pick the list according to the CIA (let’s

Read more »

Borrowing Ideas from Timely Portfolio

April 15, 2012
By
Borrowing Ideas from Timely Portfolio

I want to highlight two great Visualization techniques I discovered by reading the fine blog from Timely Portfolio. First method is based on the lm System on Nikkei with New Chart. Let’s visualize Strategy’s Long/Short/Not Invested periods by highlighting the underlying (i.e. buy & hold) with green/red/gray. Following is a sample code that implements this

Read more »

Registration for R/Finance 2012 is Open

April 15, 2012
By
Registration for R/Finance 2012 is Open

Registration has been open for a while, but I wanted to point out the pre-conference seminars. Registrations are strong this year, so if you’re interested you’ll need to sign up before they sell out. Register here… As you probably know by now, the fourth annual R/Finance conference for applied finance using R will be held

Read more »

Instrumental Variables without Traditional Instruments

April 14, 2012
By
Instrumental Variables without Traditional Instruments

Typically, regression models in empirical economic research suffer from at least one form of endogeneity bias. The classic example is economic returns to schooling, where researchers want to know how much increased levels of education affect income. Estimation using a simple linear model, regressing income on schooling, alongside a bunch of control variables, will typically

Read more »

[not] Le Monde puzzle (solution)

April 13, 2012
By
[not] Le Monde puzzle (solution)

Following the question on dinner table permutations on StackExchange (mathematics) and the reply that the right number was six, provided by hardmath, I was looking for a constructive solution how to build the resolvable 2-(20,5,1) covering. A few hours later. hardmath again came up with an answer, found in the paper Equitable Resolvable Coverings by van

Read more »

Low Volatility with R

April 12, 2012
By
Low Volatility with R

Low volatility and minimum variance strategies have been getting a lot of attention lately due to their outperformance in recent years. Let’s take a look at how we can incorporate this low volatility effect into a monthly rotational strategy with a basket of ETFs. Performance Summary from Low Volatility Test in quantstrat Starting Equity: 100,000 … Continue reading...

Read more »

In case you missed it: March 2012 Roundup

April 12, 2012
By

In case you missed them, here are some articles from March of particular interest to R users. New features in the latest version of ggplot2 include choropleths, violin plots, and improved annotations. A video demonstration of big-data Naive Bayes and Classification Tree models with Revolution R Enterprise for IBM Netezza. A collection of two-minute video tutorials for R beginners....

Read more »

Fun Editing R Graphs in Inkscape

April 12, 2012
By
Fun Editing R Graphs in Inkscape

Last week, I read a chapter out of Visualize This by Nathan Yau.  I was, of course, delighted to see that he was championing the use of R.  One really cool thing that I learned from his book, and was very … Continue reading →

Read more »

How to work with Google n-gram data sets in R using MySQL

April 12, 2012
By
How to work with Google n-gram data sets in R using MySQL

In this R tutorial you will learn how to work with Google n-gram data sets with the help of MySQL. The complete R code is included in this post.

Read more »

Nick Stokes Distance code, now with Big Memory

April 12, 2012
By
Nick Stokes Distance code, now with Big Memory

In my last post I was struggling with getting a big memory version of the distance matrix to work fast. Nick and other readers had some suggestions and after puttering around with Nicks code I’ve adapted it to big memory and not impacted the run time very much. For comparison writing a 10K by 10K

Read more »

Sponsors

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)