This combination process is referred to as triangulation (see §5).
they construct the triangulated source-target t-table t st from the source-pivot and pivot-target t-tables t sp , t pt using the following approximation: Subsequently, if a source-target corpus is available, they train a standard source-target model Θ st , and tune the interpolation with respect to λ interp to reduce alignment error rate (Koehn, 2005) over a hand-aligned development set.