Plotting conditional densities

April 14, 2012
By
Plotting conditional densities

Recently I have read a post on Comparing all quantiles of two distributions simultaneously on R-bloggers. In the post author plots two conditional density plots on one graph. I often use such a plot to visualize conditional densities of score...

Read more »

Introduction to Markov Chains and modeling DNA sequences in R

April 13, 2012
By
Introduction to Markov Chains and modeling DNA sequences in R

Markov chains are probabilistic models which can be used for the modeling of sequences given a probability distribution and then, they are also very useful for the characterization of certain parts of a DNA or protein string given for example, a bias t...

Read more »

knitr Performance Report-Attempt 1

April 13, 2012
By
knitr Performance Report-Attempt 1

I get very excited about new R packages, but rarely is my excitement so fulfilled as with knitr.  Even with no skill, I have already been able to adapt the example Yihui Xie provides in his knitr Graphics Manual into a crude first version of a per...

Read more »

Floating Point Arithmetic and The Descent into Madness

April 13, 2012
By

While I should confess upfront that I’ve always had a weaker command of the details of floating point arithmetic than I feel I ought to have, this sort of thing still blows my mind when I stumble upon it. These moments invariably make me realize that floating point math will simply never satisfy my naive

Read more »

Case Study: Network visualization with data from a 360° feedback – often wasted potential!

April 13, 2012
By
Case Study: Network visualization with data from a 360° feedback – often wasted potential!

I assume that the reader of this paper knows the 360-degree method (also known as: multi-source feedback or management feedback). Reported is an authentic case. A total of 128 people participated as feedback receivers. Several thousand questionnaires were filled from … Weiterlesen →

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 »

R Statistics Mobile Console (iPhone)

April 13, 2012
By
R Statistics Mobile Console (iPhone)

I’m trying to make a mobile version of R-GUI, here is one (trying with iPhone emulator), not so beautiful, but still work. Try at CloudStat Mobile. Below are the screenshots: Homepage Web-based R Console Statistical Apps Directory ( R Apps ) ...

Read more »

RDieHarder 0.1.2

April 13, 2012
By
RDieHarder 0.1.2

RDieHarder is an R package providing access to the DieHarder battery of tests for random number generators developed by Robert G. Brown and others. DieHarder had been updated to version 3.1.1 a while back, and I had been a little behind with updating...

Read more »

R’s continued growth in academia

April 13, 2012
By
R’s continued growth in academia

Bob Muenchen has recently updated his report on the popularity of statistical software. With the updated analysis, we see that the R community remains as strong as ever: the number of contributed R packages continues its exponential growth rate, R maintains its dominance in online discussion, and has 20x the content of other statistics packages on social programming sites...

Read more »

CORRGRAM: Correlation Matrix (Wavelengths)

April 13, 2012
By
CORRGRAM: Correlation Matrix (Wavelengths)

With the "Corrgram" package we can see patterns that can help us to recognize possible inter-correlations in a big matrix. This could be the case to see the correlation to every wavelength respect to all others. This way we can see the high correlation...

Read more »

One app, three languages

April 13, 2012
By

This past week at work I had the opportunity to code the same algorithm using each of the three scientific programming/scripting languages I'm familiar with:MatlabPythonRThe list above is the order that the (re)-coding was done and serves as a beginnin...

Read more »

Surveys measure what people do, not what people think

April 13, 2012
By

In my previous post, I wrote about ways scale choice could distort the ways survey results portray the things they are supposed to measure. This certainly isn’t a new issue – researchers who use surveys often go to great lengths to ensure that their surveys are valid and reliable, which in this context usually means

Read more »

Oracle R Enterprise 1.1 Download Available

April 13, 2012
By

Oracle just released the latest update to Oracle R Enterprise, version 1.1. This release includes the Oracle R Distribution (based on open source R, version 2.13.2), an improved server installation, and much more.  The key new features include: ...

Read more »

Oracle R Distribution 2-13.2 Update Available

April 13, 2012
By

Oracle has released an update to the Oracle R Distribution, an Oracle-supported distribution of open source R. Oracle R Distribution 2-13.2 now contains the ability to dynamically link the following libraries on both Windows and Linux: The I...

Read more »

Mebane Faber Tactical Asset Allocation in R

April 13, 2012
By

In 2006 Mebane Faber published a great piece of research detailing an asset allocation system that was both very easy to understand and implement, as well as carrying very respectable risk adjusted returns.The details are available in his paper&nb...

Read more »

US House Prices, Default and Bankruptcy Rates in R

April 13, 2012
By
US House Prices, Default and Bankruptcy Rates in R

Some time ago I got inspired by a post on r-bloggers.com, showing the housing bubble in several US cities, nicely done with ggplot. I extended this to incorporate two measures of problems in the consumer credit markets: the percentage of people with a ...

Read more »

Getting knitr to work with StatET

April 13, 2012
By
Getting knitr to work with StatET

StatET (an Eclipse plug-in that can handle, among other things, R) offers support for writing Sweave (.Rnw) documents. This is done via the external tool dialog, where one creates a new “device” that takes in a document and runs it over appropriate functions and programs. In this case, Sweave and LaTeX. This dialog can, however,

Read more »

Comparing all quantiles of two distributions simultaneously

April 13, 2012
By
Comparing all quantiles of two distributions simultaneously

Summary: A new function in the WRS package compares many quantiles of two distributions simultaneously while controlling the overall alpha error. When comparing data from two groups, approximately 99.6% of all psychological research compares the central tendency (that is a … Continue reading →

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 »

R in the CPB and the role of Open Source in Promoting Transparency and Austerity

April 12, 2012
By

The Revolution blog links to an O'Reilly  interview with two CIO's from the Consumer Protection Bureau. The gist of the interview is "Open Source is Great, we are using it for everything; R and Big Data are the next hot thing, et cetera".  I ...

Read more »

R in the CPB and the role of Open Source in Promoting Transparency and Austerity

April 12, 2012
By

The Revolution blog links to an O'Reilly  interview with two CIO's from the Consumer Protection Bureau. The gist of the interview is "Open Source is Great, we are using it for everything; R and Big Data are the next hot thing, et cetera".  I ...

Read more »

RcppArmadillo 0.3.0.1 released and on CRAN

April 12, 2012
By

Conrad Sanderson released a bug-fix version 3.0.1 following up on the very recent 3.0.0 version of his excellent Armadillo C++ template library for linear algebra. I made a new RcppArmadillo release 0.3.0.1 which just appeared on CRAN. The short ...

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 »

CORRGRAM: Correlation Matrix (Constituents)

April 12, 2012
By
CORRGRAM: Correlation Matrix (Constituents)

Thanks a lot to Kevin W., for his comment in my previous post.Corrgram, it a nice package and I found very nice information to understand it a little bit better on Internet apart from the R help page.Corrgrams: Exploratory displays for correlation matr...

Read more »

sixty two-minute r twotorials now available

April 12, 2012
By

sixty twotorials now posted. two minutes each.new video highlights:024 how to run counts, tables, crosstabs, and flat tables on a data frame in r 030 what is a function anyway and how does it input and output stuff in r 022 how to generate b...

Read more »

Ggplot2 notes part 2

April 12, 2012
By

Here is part 2 of my guide to using ggplot2. Scales Following on directly from the previous notes you can manually adjust the colours and shapes used in the chart if you don’t like the defaults, as shown in figure 1. … Continue reading &#8...

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 »

M-O-M vs Y-O-Y inflation rates in India

April 12, 2012
By
M-O-M vs Y-O-Y inflation rates in India

Some time back I came across this article, by one of our alumni who is currently at NIPFP, which presents some caveats and shortcomings of different measure of inflation in India in a concise manner. Since my master's thesis topic revolves around infla...

Read more »

Statistical Software Popularity on Google Scholar

April 12, 2012
By
Statistical Software Popularity on Google Scholar

Background (probably boring) Several months ago, my boss and I were discussing how he got the data for his software popularity article; the rest of the background discussion pertains to those plots, so I would recommend going over to take a look before continuing on (or just skip to the next section if you're impatient).  Specifically, we were talking...

Read more »