VTT decision surface for test data. Decision boundary for VTT on the space of P(a)/N(a) and np(a) for the test abstracts. Red and blue dots represent negative and positive abstracts. Dotted line represents surface that optimizes training data alone. VTT, variable trigonometric threshold.
Abi-Haidar et al. Genome Biology 2008 9(Suppl 2):S11 doi:10.1186/gb-2008-9-s2-s11