As far as I can tell, Gove et al. (2002) might be a good example for
benchmarking the optimization performance of R vs. ADMB. It would be great
if expert R users/developers could tweak Beni's model so that the
performance comparison is valid.
The main purpose is not to see which is faster or more reliable, but to
quantify how much performance is gained by moving from R to ADMB.
I have just typed and uploaded an excerpt from an old but thorough
benchmark, where ADMB outperformed Gauss, Matlab, and S-Plus
(http://admb-project.org/community/benchmarks/optimization). The benchmark
was performed in 1997 and an update would be very valuable, as software
and hardware have improved since then.
R is an interpreted language that can do just about anything. ADMB is a
compiled language (thin layer on top of C++) that does optimization and
nothing else. I don't think it is a realistic goal for R to match the
optimizing performance of ADMB. I use R for most of my work, but crunch
numbers with ADMB when computational speed and flexibility become an
issue.
As an analogy, data frames in R are great, along with functions like
aggregate(), apply(), merge(), and xtabs(). But when the tables are too
large and too many, it's time to delegate the problem to a relational
database.
In the case of model X, which is already implemented in R, it may take
half an hour or half a month to convert it to ADMB, and the payoff depends
on how often the model needs to be run. In the case of model Y, which is
not yet implemented, some users may be quicker to implement it in R than
in ADMB, so again it would be good to have an idea about the relative
performance gain. Model Z may not run at all in R, due to its size and
complexity.
Although I started this email with "R vs. ADMB", my daily working
environment is better described as "R and ADMB". I'm a regular contributor
to both R (4 packages and a couple of functions in the base packages) and
ADMB (dev core team). Others have contributed R packages to interface with
ADMB
(http://admb-project.org/community/admb-meeting-march-29-31/InterfacingADMBwithR.pdf/at_download/file),
but for many the interface is just reading and writing text files.
I fully appreciate the comfort and efficiency of the R working
environment, and the benefits of performing most tasks inside the same
environment. But the R community has no need to be on the defense against
ADMB, any more than against relational databases. If you work with
computationally intensive models, I encourage you to try out ADMB
(admb-project.org, free software) and hopefully end up contributing ideas
and/or code.
Best regards,
Arni
P.S. Phew. Future emails mentioning ADMB on r-help can be more brief and
to the point, citing this message for details.
Windows ADMB-IDE installer
http://code.google.com/p/admb-project/downloads/list?q=ide*exe
Windows, Linux, and Mac OS standalone
http://code.google.com/p/admb-project/downloads/list?q=windows
http://code.google.com/p/admb-project/downloads/list?q=linux
http://code.google.com/p/admb-project/downloads/list?q=macos
ADMB modes for various editors, including Emacs and Vim
http://admb-project.org/community/editing-tools
______________________________________________
R-help@r-project.org mailing list
https://stat.ethz.ch/mailman/listinfo/r-help
PLEASE do read the posting guide http://www.R-project.org/posting-guide.html
and provide commented, minimal, self-contained, reproducible code.
