Blog Archives

ipython notebook for R: Quickstart for Ubuntu

October 27, 2013
By

If you’re like me, you love ipython notebook but often write R.  RStudio’s integrated RMarkdown is nice, but for some contexts like quick demos or basic training, a browser-based interface is unbeatable.  What if we could get the best of… Read more ›

Read more »

Is the Tax Code the longest Title?

August 19, 2013
By
Is the Tax Code the longest Title?

  Last week, I shared that Dan Katz and I had finally published a draft of our paper, Measuring the Complexity of the Law: The U.S. Code.  We’d previewed this research on Computational Legal Studies years ago.  Since then, we’ve received great… Read more ›

Read more »

Plotting average read and write operation size by ASM disk for Oracle

June 12, 2013
By
Plotting average read and write operation size by ASM disk for Oracle

  Throughput, throughput, throughput – for many databases, this is the performance measure of importance.  When you are working with a fixed number of IOPS but see mixed workload types, system health can be assessed through the average read and…Read more ›

Read more »

Plotting Oracle RMAN backup durations with R

June 3, 2013
By
Plotting Oracle RMAN backup durations with R

  How long does your Oracle RMAN backup take to complete?  How does this vary over time?  Are there patterns by week, week of month, or day of week?   The gist below can help you evaluate questions like these.… Read more ›

Read more »

Revisiting text processing with R and Python

May 25, 2013
By

  Back in 2011, I covered the relative performance difference of the most popular libraries for text processing in R and Python.   In case you can’t guess the answer, Python and NLTK  won by a significant margin over R and… Read more ›

Read more »

Connecting R to an Oracle database with RJDBC

November 22, 2012
By

In many circumstances, you might want to connect R directly to a database to store and retrieve data.  If the source database is an Oracle database, you have a number of options: ROracle RODBC RJDBC   Using ROracle should theoretically… Read more ›

Read more »

Retrieving the VIX term structure in R

November 5, 2012
By

  Much of my time lately has gone into analyzing and trading products in the volatility complex.  As a result, I regularly watch the VIX term structure for continuations or deviations from trend.  To make analysis simpler, I’ve written some… Read more ›

Read more »

Debugging parameter mismatch across RAC database instances with R, dba_hist, and gv$parameter

October 9, 2012
By
Debugging parameter mismatch across RAC database instances with R, dba_hist, and gv$parameter

Did you find this post useful?  Does your organization need Oracle services?  We can help.   Much of this morning went into investigating strange ADDM reports on a two-node Oracle RAC database.  For some reason, there were statistically improbable differences…Read more ›

Read more »

Wordcloud of the Arizona et al. v. United States opinion

June 25, 2012
By
Wordcloud of the Arizona et al. v. United States opinion

Here’s one purely for fun – a wordcloud built from the Supreme Court’s opinion on Arizona et al. v United States.  Word clouds, though certainly not the most scientific of visualization techniques, are often engaging and “fun” ways to lead…Read more ›

Read more »

Summary of community detection algorithms in igraph 0.6

June 17, 2012
By

  Based on Launchpad traffic and mailing list responses, Gabor and Tamas will soon be releasing igraph 0.6.  In celebration, I’ll be publishing a number of helpful lists and tables I’ve put together to organize information about igraph.   In…Read more ›

Read more »