Data re-use update

In a previous post, I noted 5 cases of data re-use in the stripy articles. This has already led to two corrections, one in PNAS and one in Nature Materials.

Two of those cases concerned Journal of Scanning Probe Microscopy, 2009, 4, 1–11 which re-used images from both J Am Chem Soc, 2006, 128, 11135-11149 and J. Phys. Chem. C 2008,112, 6279-6284. I noted that:

Cases 3 and 4 together indicate that all of the experimental STM figures in paper 2 (i.e. Fig 2-5) contain data re-use (from two different articles).

The raw data released last week reveal that the data analysis section  (i.e. Fig 6-8) of that same Journal of Scanning Probe Microscopy article is also based on previously published data… but from a third paper (Nature Materials, 2004,3, 330-336). The re-analysis of previously published data is of course a perfectly acceptable activity if the figure legends or text indicate clearly where the data analyzed come from which is unfortunately not the case here.

The method section of that article starts with “The synthesis procedures used for the particles described in this paper are derived from previous reports”. A more accurate version would have read: “The images presented or analyzed in this paper are extracted from previous papers” (note the ‘or’ since the images ‘presented’ were coming from different papers than those which were ‘analysed’).

This Journal of Scanning Probe Microscopy article is quoted several times in the Response to Stripy Nanoparticle Revisited to show that the authors have “performed a full regression analysis to statistically validate and support our conclusions“. This analysis will be the topic of another post.

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6 thoughts on “Data re-use update

  1. The data is rather strange, assuming (it is hard to tell from the way the paper is written and I only skimmed the section on figure 3) he is using the microscope under normal constant current operation, the current image should in theory be flat. Any features in the current image are your error in maintaining a constant current (by changing height to get the topography image). Some hint of the features always bleed into the current image as it is impossible to get perfect feedback. The fact that the stripes are clearer in the current image, than in the topography really indicate that the integral gain is up to high causing the feedback to be unstable. This instability is clear also from the random streaks in the image. Strong stripes in the topography which are not visible in the current image would be evidence for a real feature.

  2. Pingback: The stripy controversy as a window into the scientific process* | Rapha-z-lab

  3. Pingback: Why we are very unlikely to see an admission that the 2004 paper is based on an artifact, let alone retracted | Rapha-z-lab

  4. The 2008 paper does at least show a comparison of homoligand to stripey images. And one set looks smooth while the other has faint stripes. However, based on previous discussion of how stripes not apparent in raw data, but only after image processing…it concerns me that small tweaks in contrast, etc. could create the faint stripes in one and not the other. And if you know which image is which (this is not blinded bio research), you can try to get the right features, versus just trying to image most accurately and what is there is there. Just a concern.

    Furthermore, the subsequent “independent” imaging didn’t even show faint stripes…just everything smooth eggs and needing some statistics to argue for very faint stripes.

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