title: On the A-optimality criterion for finding two-color microarray optimal designs.
abstract: Several studies on two-color microarray experimental designs consider the A-optimality criterion for the assessment and/or search of appropriate/optimal designs. What seems to be widely ignored, however, is the well-known fact that A-optimal designs depend on the choice of scale or code combination of the X-variables. In this article, it is shown that intrinsically different optimal microarray designs will be obtained depending on the chosen code combination of the qualitative factors. Moreover, a substantial loss in efficiency will result when a design, which is optimal for a specific code combination, is used for another one. This coding problematic is also applicable to the admissibility concept.
authors.affiliation: Department of Methodology and Statistics, Maastricht University, Maastricht, The Netherlands. frans.tan@maastrichtuniversity.nl
authors.forename: Frans E S
authors.initials: FE
authors.lastname: Tan
authors.forename: Valéria Lima
authors.initials: VL
authors.lastname: Passos
mesh_terms: D000465:Algorithms; D003627:Data Interpretation, Statistical; D020869:Gene Expression Profiling / Q000379:methods; D016014:Linear Models; D020411:Oligonucleotide Array Sequence Analysis / Q000295:instrumentation / Q000379:methods*; D012107:Research Design