Publications by Jason

Using R and snow on Ohio Supercomputer Center’s Glenn cluster

28.03.2011

Over the last several days, I have had the “pleasure” of getting parallel processing with R running on the the Ohio Supercomputer Center’s (OSC) Glenn cluster. I am working on a project that uses GenMatch from Sekhon’s Matching, which uses the snow library to manage parallel processing. Getting snow to run properly on single machines, or ...

3855 sym R (1544 sym/11 pcs)

A very short and unoriginal introduction to snow

02.04.2011

As Jian-Feng rightly pointed out in a comment on my guide to setting up snow on the OSC cluster, it was probably somewhat cavalier of me to say: Getting snow to run properly on single machines, or ever with a cluster of machines via ssh connections is fairly trivial. In an effort to redeem myself, I provide this very short and unoriginal in...

4395 sym R (358 sym/7 pcs)

A simple frequency plot

08.04.2011

I’m currently working on a paper that uses Polish survey data (EVS 2008). I am specifically looking at regional variation in particular responses. Because there are only around 1800 observations in the survey, which are split across 66 subregions of Poland (NUTS-3, specifically), I suspected there would be a large degree of variation in how the...

2102 sym R (356 sym/2 pcs) 2 img

Code: mtable-ext updated

21.06.2011

I have fixed a small bug in mtable-ext that prevented asterisks from being printed for negative coefficients in mixed effects models output by lme4. Thanks to Reinhold Kliegl and Martin Elff for pointing out the bug and for providing the fix. The updated code can be found below. However, I do want to warn users that the way the code calculates p...

1019 sym

The performance cost of a for-loop, and some alternatives

21.08.2011

I’ve recently been spending a lot of time running various simulations in R. Because I often use snow to perform simulations across several computers/cores, results typically come back in the form of a list object. Summarizing the results from a list is simple enough using a for-loop, but it’s much “sexier” to use a functional style of pr...

4196 sym R (3055 sym/7 pcs)

Three free books for better programming in R (and any other language)

19.09.2011

Like many users and producers of R packages, I have never had any formal training in computer science. I’ve come to to the conclusion that this is a serious omission in a professional researcher’s training. Computer scientists and professional hackers have learned a lot about effective, efficient programming over the last five decades and it�...

2117 sym

Managing a Local R Repository

10.11.2011

I will be teaching a workshop on R and LaTeX at NEAIR in just under a month. One of the issues I will encounter is a lack of Internet access. I also work with restricted data from NCES which requires the computer to be secured including no network access. As such, I need to manage software from removable media. I have written some functions th...

1657 sym

Visualizing Likert Items

11.11.2011

I have become quite a big fan of graphics that combine the features of traditional figures (e.g. bar charts, histograms, etc.) with tables. That is, the combination of numerical results with a visual representation has been quite useful for exploring descriptive statistics. I have wrapped two of my favorites (build around ggplot2) and included ...

930 sym R (1582 sym/2 pcs) 2 img

Retrieving RSS Feeds Using Google Reader

13.01.2012

I have been working on a new package makeR to help manage Sweave projects where you wish to create multiple versions of documents that are based on a single source. For example, I create lots of monthly and quarterly reports using Sweave and the only differences between versions are a few variables. I have used GNU make and Apache ANT but wanted...

1450 sym R (4913 sym/2 pcs) 4 img

Announcing boolean3 (beta)

24.01.2012

After entirely too long, I am happy to announce the beta release of boolean3, an R package for modeling causal complexity. The package can be downloaded at the following links: Unix/Linux: boolean3_3.0.20.tar.gz Windows: boolean3_3.0.20.zip (Please let me know if you have any trouble installing the Windows version. I didn’t have a Windows s...

2877 sym Python (544 sym/2 pcs)