Experimental Research Hints

(Or, things I wish I'd known my first year of grad school)

Write It Down!

At some point, you will run experiments and later need to reference it in a paper or progress report (or someone else in your research group needs to understand the experiment). You will be very happy if you have logged some of the following:

motivation for the experiment
expectations you had before running the experiment
parameters used in the experiment
general impression of the results

Lab notebooks are valuable, but web pages are great places to record this type of information. Not only can you search for keywords, but you can refer others to your log and link in other documents (plus, if it's in AFS-space, it's backed-up). Often people will put pictures of graphs and other results on their experiment web page. Here's my online experiment log.

Essential Tools

gnuplot is my favorite plotting utility (FAQ, Intro from UNI). Lots of people at UNC also use Matlab.

awk is a great little scripting language. I use it mainly for separating columns from data files. Here's an example:

# test.dat
123 abc 456 efg 789 hij
321 cba 654 gfe 987 jih

% awk '{print $1,$3,$5}' < test.dat

123 456 789
321 654 987

% awk '{if ($1==123) print}' < test.dat

123 abc 456 efg 789 hij

Here are a couple of awk tutorials: rice.edu, canberra.edu.au

learn perl or python

Help with References

During the course of grad school, you'll read lots of papers. You'll even want to remember something about many of these papers. Starting an annotated bibliography early will help you when you're ready to write a paper, your proposal, the related work section of your dissertation, anything.

You can either start a Word document with references and comments, or use BibTeX. If you have any inkling that you want to write papers and/or your dissertation in LaTeX, use BibTeX for your references. (Here's my BibTeX setup.) If you want to use Word, several folks at UNC use EndNote for organizing bibliographies (it's not free, but is sold at Student Stores).

Archival Data Storage is Plentiful

After you've run lots of experiments, you may find you need additional disk space. ATN offers a mass storage system that uses SAM-FS. After your data has been in the mass storage system for 14 hours, it is backed up to tape. Note that this system is only for long-term storage of seldom-used files.

Recommending Reading

The Art of Computer Systems Performance Analysis: Techniques for Experimental Design, Measurement, Simulation, and Modeling by Raj Jain (UNC libraries, amazon.com)
Writing for Computer Science: The Art of Effective Communication by Justin Zobel (amazon.com)

Michele Weigle
mcweigle@cs.unc.edu