Special thanks go to John Quackenbush and Hernan Ortiz Molina for helpful comments and to Biomarkers in Transplantation's members, Alice Mui, Janet McManus, Pooran Quasimi, David Lin, Axel Bergman and Martha Casey-Knight, for useful discussions. We would also like to thank Tim Triche, Jonathan Buckley and Betty Schaub from MAC lab for processing the Transplantation samples and discussing its quality measures with us. G. C. F. is supported by an IBM Institutes of Innovation Fellowship Award.
Conflict of Interest: none declared.
Associate Editor: Joaquin Dopazo
1 Note that the QC report may also contain some non-numeric measure (e.g. ‘Spikes Decr’ in GCOS QC reports) that should be inspected separately.
2 Robust PCA methods when p > n can be found in Huber et al. (2002).
3 Note that the ID numbers used here are not the same as the ones used in previous references. However, array 2 in this study corresponds to array a in Bolstad et al. (2005) and 15 in Brettschneider et al. (2007).
Received on June 6, 2007; revised on September 6, 2007; accepted on September 25, 2007