Rubbish in, Garbage Out?

Extraordinary claims require extraordinary press releases?

You have probably read a headline in the past few weeks stating that NASA has verified that an infamous, seemingly reactionless propulsion drive does in fact produce force. You also might not have read the technical report that spurred the media frenzy (relative to the amount of press coverage normally allocated to space propulsion research, anyway), instead relying on the media reports and their own contracted expert opinion. The twist is that it seems to be the case that no one else- excepting perhaps the participants of the conference it was presented at– has read it either, and this includes myself and likely the authors of almost any other material you find commenting on it. The reason is that the associated entry in the NASA Technical Reports Server only consists of an abstract.

The current upswing of interest and associated speculation on the matter of this strange drive is eerily reminiscent of other recent \begin{sarcasm}groundbreaking discoveries\end{sarcasm}: FTL neutrinos measured by the OPERA experiment and the Arsenic Life bacterium from Mono Lake, California. Both were later refuted, some important people at OPERA ended up resigning, and the Arsenic Life paper continues to boost the impact factors of the authors and publisher as Science Magazine refuses to retract it. (current citations according to Google Scholar number more than 300).

I would venture that the manner of disclosing the OPERA findings was done more responsibly than the Arsenic Life paper. Although both research teams made use of press releases to gain a broad audience for their findings (note this down in your lab notebook as “do not do” if you are a researcher), the OPERA findings were at the pre-publication stage and disclosed as an invitation to greater scrutiny of their instrumentation, while the arsenic life strategy was much less reserved. From the OPERA press release:

The OPERA measurement is at odds with well-established laws of nature, though science frequently progresses by overthrowing the established paradigms. For this reason, many searches have been made for deviations from Einstein’s theory of relativity, so far not finding any such evidence. The strong constraints arising from these observations makes an interpretation of the OPERA measurement in terms of modification of Einstein’s theory unlikely, and give further strong reason to seek new independent measurements.

Notice the description of the search for exceptions to Einstein’s relativity as ” . . . so far not finding any evidence. . .” That despite the data they are reporting doing exactly that if anomalous instrumentation could be ruled out. This was a plea for help, not a claim of triumph.

On the contrary, the press seminar associated with the release of Felisa Wolfe-Simon et al.’s A bacterium that can grow by using arsenic instead of phosphorus issued no such caveats with their claims. Likewise it was readily apparent in the methods sections of their paper that the Arsenic Life team made no strong efforts to refute their own data (the principal aim of experimentation), and the review process at Science should probably have been made more rigorous than standard practice. It is perhaps repeated too often without consideration, but I’ll mention the late, great Carl Sagan’s assertion that “extraordinary claims require extraordinary evidence.” The OPERA team kept this in mind, while the Arsenic Life paper showed a strong preference to sweep under the carpet any due diligence in considering alternative explanations. Ultimately, the OPERA results were explained as an instrumentation error and the Arsenic Life discovery has been refuted in several independent follow-up experiments (i.e. [1][2]).

Is propellant-less propulsion on par with Arsenic Life or FTL neutrinos in terms of communicating findings? In this case I would lean toward the latter: more of a search for instrumentation error than a claim of the discovery of Totally New Physics. The title of the tech report “Anomalous Thrust Production from an RF Test Device Measured on a Low-Thrust Torsion Pendulum” denotes the minimum requisite dose of skepticism.

Background reading below, but by far the best take on the subject is xkcd number 1404. The alt-text: “I don’t understand the things you do, and you may therefore represent an interaction with the quantum vacuum virtual plasma.”

23/08/2014 several typos corrected
[UPDATE Full version of tech report: via comments from . . . . . . . .

A Phylogeny of Internet Journalism

While reading press coverage on the UW-Madison primate caloric restriction study for my essay, I kept getting deja vu as I noticed I was coming across the same language over and over. Much of this was due to the heavy reliance of early coverage on the press release from the University of Wisconsin-Madison, and sites buying stories from each other,and I decided it might be informative to make a phylogenetic tree of the coverage. To do so I used the text from the first two pages of google news results for “wisconsin monkey caloric restriction” and built a phylogenetic tree based on multiple sequence alignment after converting the english text to DNA sequences. I found a total of 27 articles on the CR study, and included one unrelated outgroup for a total of 28.

I used DNA Writer by Lensyl Urbano (CC BY NC SA) to convert the text of the article into a DNA sequence. This algorithm associates each character with a three nucleotide sequence, just like our own genome defines amino acids with a three letter code. Unlike our own genetic code, Urbano’s tool is not degenerate (each letter has only one corresponding 3 letter code). With base four (Adenine, Thymine, Guanine, and Cytosine provide our bases) there is room for 4^3 (64) unique codes. For example “I want to ride my bicycle” becomes


The translation table and tool are available at

To build the trees and alignments I used MAFFT. The sequences derived from each article can be relatively long, and MAFFT can handle longer sequences due to its use of the Fast Fourier Transform. MAFFT is available for download or use through a web interface here. I used the web interface, checking the Accurate and Minimum Linkage run options.

Once I had copied the tree in Nexus format, I ran FigTree by Andrew Rambaut to generate a useful graphical tree. I had included an unrelated article at Scientific American as an outgroup, and I chose the branch between that article and the group composed of press coverage of the UW macaque caloric restriction study as the root. This would correspond to a last common ancestor on a real phylogeny tree.

The resulting tree produces some interesting clades, for example ScienceDaily, esciencenews, and News-Medical, who essentially all just reproduced the UW-Madison press release, are grouped together. Another obvious group is the Tampa Bay Times and the Herald Tribune, which sourced the article from the New York Times and pared it down for their readers.


Here is the tree in Nexus format:


. . .and this is a list of all the addresses for the articles I used and their labels on the tree:…logenetic-tree/