It has come to our attention that the Academic Editor who handled this manuscript, Dr Mariano Sigman, co-authored several publications with one of the authors of the article in the five years that preceded the submission to PLOS ONE.
In line with the PLOS ONE competing interests policy (http://www.plosone.org/st...), we consider this as a potential conflict of interest. Dr Sigman was invited by PLOS ONE to act as Academic Editor for this manuscript and we acknowledge that the journal should not have approached him to handle this manuscript.
We have asked an independent Academic Editor, Professor Keith Laws, to carefully evaluate the peer review process of this article. Professor Laws has confirmed that he is satisfied that the decision for publication was adequate.
