[Final, summary post.] I thought I should post some notes about the responses to Andrea’s recent postings. Several people seem to have extrapolated beyond what Andrea said.
After a few months of the Cardini, O’Higgins, Rohlf, and Bookstein collaboration (Polly was CC:ed on the very early emails but I do not remember him engaging), I suggested to Andrea that there should be two publications not one. I could see that while writing about the same flaws in the same method the approaches Fred and I were taking would be difficult to combine in the same paper. Andrea and Paul agreed and Andrea then suggested to Fred that he write a paper separate from ours. Thus, Fred did not unilaterally jump ahead and just write his own paper as some seem to have assumed. The understanding was that we expected the two papers to be published together as “companion papers” in some journal yet to be determined. I know that Fred was concerned about the ethics of waiting a long time to warn people that they were using a severely flawed (I would say strongly biased) method. The usage of BG-PCA seems to have increased lately and it did not seem fair to let people continue to write papers and dissertations based on this method once we knew how bad it was. His biorxiv upload and his announcement of it on morphmet were not a surprise to us. There were emails exchanged about the need to warn users. At the time, Fred told me that he needed to go ahead with the biorxiv upload as it was unclear how long it would take our ms. to be completed due to other demands on our time. Reading Fred’s papers can take time but if one just looks at his Fig. 1 (Google "biorxiv 627448" if you lost the link that Fred posted) you will see the magnitude of the problem. It is not subtle! Incidentally, the Cardini et al. draft also has a more extensive Figure illustrating the same problem as a function of n but the rest of the paper is very different. In fact, I found it interesting how two papers about the same defect in the same method and reaching the same conclusion could have so little overlap. Thus, Fred’s paper does not infringe on the content of the Cardini et al. manuscript or interfere with its publication – in fact I think it makes it more important as it will show the problem does not require an understanding of an abstract theorem. I believe the Cardini et al. paper will show that the defects in the method are very easy to understand and obvious once you think about it in the right way. ____________________________________________ F. James Rohlf, Distinguished Professor, Emeritus. Ecology & Evolution Research Professor, Anthropology Stony Brook University -- MORPHMET may be accessed via its webpage at http://www.morphometrics.org --- You received this message because you are subscribed to the Google Groups "MORPHMET" group. To unsubscribe from this group and stop receiving emails from it, send an email to morphmet+unsubscr...@morphometrics.org.