A couple of weeks ago, I attended the 5th .Astronomy meeting, which took place in Boston. For anyone not familiar with this series of conferences, the aim is to bring together researchers, developers, and educators/outreach specialists who use or are interested in using the web as a tool for their work (I like to think of it as an astro-hipster conference!).

One of the topics that comes up regularly at .Astronomy meetings is the question of credit: how do we, as scientists, get credit for work that is not considered 'traditional', such as (but not limited to) creating or contributing to open source software, outreach activities, or refereeing? Sarah Kendrew already summarized the discussions on this topic in her blog, so I won't repeat them here. However, given that I contribute to a number of open source projects (such as Astropy, APLpy, and many others) this got me wondering how often authors actually acknowledge the tools that they use in papers?

I previously played around with the NASA/ADS full-text search, but what I wanted was a way to be able to do this automatically for any keyword/phrase, and be able to see the evolution of acknowledgments over time. With the release of the ADS developer API (which Alberto Accomazzi presented on the Monday at .Astronomy), I finally had the tool I needed to do this! This was a fun post-dotastro hack, for which I now present the results below.

The code

Since not everyone reading this will be interested in the code I used to do this, I have placed it in a separate IPython notebook that you can access here. Please feel free to fork and contribute to it!

The results

Let's start off by looking at how often ADS itself is acknowledged. The suggested acknowledgment phrase includes Astrophysics Data System, so we will search for that:

This shows that more and more people are acknowledging ADS, but that even now this represents less than 1% of all papers! Of course, many people, myself included (until now), use ADS without thinking about acknowledging it, but this illustrates to what extend we are under-acknowledging what we use to do our research and write papers.

Let's move on to common online databases, such as Simbad, Vizier, and NED:

I want you to take a look at the y scale. At most 0.17% of refereed papers currently acknowledge using SIMBAD. Now I know there are quite a few theorists out there, but this is a little on the low side... As was the case for ADS, it's encouraging to see that the fraction is increasing over time, but if we extrapolate the increase since the year 2000, it will take another two thousand years before 10% of papers acknowledge the use of SIMBAD (and I'm sure the real value should be higher).

Moving on to programming languages:

The fractions are even smaller than the online databases above, although in all fairness there is no requirement to acknowledge programming languages directly, so I will not complain about this. What is interesting though are the trends. IDL and Fortran both see a large drop in fraction of acknowledgments this year, while mentions of Python have seen a sharp increase from almost none around 2005 to more than any of the other languages shown here. While this is a poor metric of which languages people are actually using, it does show that the uptake of Python over the last few years is very encouraging!

Finally, let's wrap up with a few common tools:

Again, the fractions are far too low compared to the real usage, but the trends are again very instructive. IRAF and Starlink are now past their peak, while Ds9, Aladin, and Topcat are all on the rise!

Take-home message

Most of the services and tools I have shown results for above actually have standard phrases that you can add to the acknowledgment section of your latest paper, but it's clear that most papers are not following these guidelines. This is a severe problem because for some of these projects, funding may be dependent on the level of use, and for volunteers it may be the only way they can get credit for their work.

People may ask where acknowledgments should stop - should also acknowledge LaTeX, Apple, or the use of Fourier transforms? Of course not. In my view, the line should be drawn at the point where we think that these acknowledgments matter and will make a difference to projects in our community. All of the examples above are ones that should be acknowledged, and it is also crucial that you think of acknowledging smaller software packages that you use, especially if the developers have provided a standard phrase. Yes, your acknowledgment section may become quite long, but this is not about esthetics - it is something that may make a real difference to some of these projects.

Of course, you don't want to spend hours searching around for all the possible acknowledgments on the web, but fear not! AstroBetter now hosts an acknowledgment wiki on which you will find many acknowledgments - this list is far from exhaustive, so please add to it any acknowledgment you are aware of!

In the mean time, what do you think about the low fractions of acknowledgments? How can we encourage more people in our community to fairly acknowledge the tools and services we use?