Anything You Can Do, I Can Do Better (No You Can’t)…

Some more interesting reading:

K. Price, Anything You Can Do, I Can Do Better (No You Can’t)…, Computer Vision, Graphics, and Image Processing, Vol. 36, pp. 387-391, 1986, doi:10.1016/0734-189X(86)90083-6.

Abstract: Computer vision suffers from an overload of written information but a dearth of good evaluations and comparisons. This paper discusses why some of the problems arise and offers some guidelines we should all follow.

Very nice reading material, and (although I know these ideas are around for quite some time already) I was amazed to see so many parallels to our recent IEEE Signal Processing Magazine paper, already in this paper by Price from 1986. That’s more than 20 years ago! Price talks about the reproducibility problems in computer vision and image processing, writing we should “stand on other’s shoulders, not on other’s toes”. He also did a study on reproducibility of a set of about 42 papers, verifying the size of the dataset and clarity of the problem statement. Price concludes as follows: “Researchers should make the effort to obtain implementations of other researchers’ systems so that we can better understand the limitations of our own work.”

Again, interesting to see how these issues and worries have been around for more than 20 years in the field of image processing. It’s about time to drastically improve our standards, I think!

I would really recommend this article to anyone interested in issues around reproducible research.

Literate Statistical Practice

I just read the following paper:

A. J. Rossini and F. Leisch, Literate statistical practice, UW Biostatistics Working Paper Series 194, University of Washington, WA, USA, 2003.

Although I am not a statistician, this was a very interesting paper to me. It gives a nice description of a possible literate programming approach in statistics. The authors propose a very versatile type of document combining documentation and code/statistical analyses, interweaved as in the original description of literate programming by Knuth. From this versatile document, which contains a complete description of the research work, multiple reports can be extracted, such as an article, an internal report, an overview of the various analyses that were performed, etc.

Challenges and Prizes

I just read the article about Netflix’ Million Dollar Programming Prize on IEEE Spectrum.

Robert M. Bell, Jim Bennett, Yehuda Koren, and Chris Volinsky, The Million Dollar Programming Prize, IEEE Spectrum Online, http://www.spectrum.ieee.org/may09/8788.

Interesting article, showing again how contests proposing a challenge can inspire a lot of great work, and allow an ‘objective’ comparison between algorithms. I think they provide a great way to motivate researchers to work on real problems, with testing on standardized datasets.

Reproducible Research in Signal Processing - What, why, and how

I am glad to let you know that our paper has been published in the latest issue of IEEE Signal Processing Magazine:

P. Vandewalle, J. Kovacevic and M. Vetterli, Reproducible Research in Signal Processing - What, why, and how, IEEE Signal Processing Magazine, Vol. 26, Nr. 3, pp. 37-47, 2009, DOI: 10.1109/MSP.2009.932122.

Have you ever tried to reproduce the results presented in a research paper? For many of our current publications, this would unfortunately be a challenging task. For a computational algorithm, details such as the exact data set, initialization or termination procedures, and precise parameter values are often omitted in the publication for various reasons, such as a lack of space, a lack of self-discipline, or an apparent lack of interest to the readers, to name a few. This makes it difficult, if not impossible, for someone else to obtain the same results. In our experience, it is often even worse as even we are not always able to reproduce our own experiments, making it difficult to answer questions from colleagues about details. Following are some examples of e-mails we have received: “I just read your paper X. It is very completely described, however I am confused by Y. Could you provide the implementation code to me for reference if possible?” “Hi! I am also working on a project related to X. I have implemented your algorithm but cannot get the same results as described in your paper. Which values should I use for parameters Y and Z?”

Enjoy reading! And feel free to post your comments!

A sobering experience

Last month, a few former colleagues at LCAV did some cross-testing of the reproducible research compendia available at rr.epfl.ch. And I must say, from the results I have seen so far, it is quite a sobering experience. Many of those which I considered to be definitely reproducible didn’t pass the test (entirely). I guess that shows again how difficult it is to make work really reproducible, even if you fully intend to do it. So that also leads me to my conviction that for papers that do not have code and data online, it is almost impossible to reproduce the exact results. There is work to be done on the road to reproducible research!

I’ll need to look further into the reasons why even some of my own work did not pass the test.

reproducibleresearch.net

I am glad to announce you our new website on reproducible research: www.reproducibleresearch.net. Yes, as I already discussed before, various sites on this topic recently (or less recently) popped up. However, I still think this site can add something extra to the existing sites. First of all, it is mainly addressing the signal/image processing community, a research domain not specifically addressed in the other sites yet.

It contains information on reproducible research and how to make signal processing research reproducible. It also lists references to articles about reproducible research, a discussion forum, and various other related links.

And then, in my opinion an important extra to signal processing interested people. We added a listing of links to papers for which code/data are available (with of course links to them). I really believe this can be extremely useful when doing research. For copyright reasons, we cannot (in most cases) host the PDF on our own site, and I am also not sure we should want to. But if developed and maintained well, this can give a one-stop site when looking for code/data related to a paper. So please feel free to send me your additions. I will be happy to add all signal/image processing related works!

I’m really excited about this site, so let me know what you think!

Computing in Science & Engineering

The current issue of Computing in Science and Engineering (CiSE) is a special issue on reproducible research, edited by two pioneers in the field: Jon Claerbout and Sergey Fomel. They have assembled a great set of articles from experts with a lot of first-hand, personal reproducible research experience, so I would highly recommend this to my colleague researchers!

New York Times about R

I got a pointer earlier this week to a New York Times article about R. A very interesting article about the use of R in scientific communities and industrial research, mainly for statistical analysis. R is open source software, so it is free and has already taken advantage from contributions made by various authors. And (although I haven’t used it myself yet), it is a great tool for reproducible research. Using the package Sweave, authors can write a single document containing their article and the R code to reproduce the results and put them in place. This ensures that all the material is in a single place.

It also shows something about the amazing power of open source software developed by a community of authors (and typically users at the same time).

Domain names

I seem to be dwelling quite some time on the web lately… After my post about the lifetime of URLs, here’s one about domain names and reproducibility. I recently noticed when looking around that there are quite some websites and domain names related to reproducible research.

reproducibleresearch.org is an overview website by John D. Cook containing links to reproducible research projects, articles about the topics, and relevant tools. It also contains a blog about reproducible ideas.

reproducibleresearch.com is owned by the people at Blue Reference, who created Inference for Office, a commercial tool to perform reproducible research from within Microsoft Office.

reproducibility.org is used by Sergey Fomel and his colleagues as home for their Madagascar open source package for reproducible research experiments.

reproducible.org is a reproducible research archive maintained by R. Peng at Johns Hopkins School, where the goal is to host a place for reproducible research packages.

Quite a range of domain names containing the word “reproducible” (or a derivative), if you ask me! And then I didn’t even start about the Open Research or Research 2.0 sites. Let’s hope this also means that research itself will soon see a big boost in reproducibility!

2009

Let me in my turn wish you all the best for 2009! I wish you a beautiful, entirely non-reproducible year with lots of great experiences!

2008 was the year in which this site got started, and to be honest, I am quite happy with the frequency at which I managed to post articles here. In its first year, the site also obtained a reasonably good visibility on Google, so nothing to complain about. It does remain to a large extent a one-way communication, but as I hear from colleague bloggers, that is not uncommon. Let me at the start of this year invite you again: if you read this blog, and like or dislike something I write, please post a comment! It will encourage me to continue writing, and make me feel a bit less lost in blogosphere.

And up to a wonderful 2009 now!