Algorithm and Data Analysis, Affymetrix Inc. 3420 Central Expressway, Santa Clara, California, USA. ke_hao@affymetrix.com|Algorithm and Data Analysis, Affymetrix Inc. 3420 Central Expressway, Santa Clara, California, USA. ke_hao@affymetrix.com|Algorithm and Data Analysis, Affymetrix Inc. 3420 Central Expressway, Santa Clara, California, USA. ke_hao@affymetrix.com