This is illustrated by the following example (from the IWSLT 2007 Arabic-English translation task): Source 1: Asf lA ymknk *lk hnAk klfp HwAly vmAnyn dwlAr lAlsAEp AlwAHdp Ref: sorry you can't there is a cost the charge is eighty dollars per hour 1-best: i'm sorry you can't there in the cost about eighty dollars for a one o'clock Source 2: E*rA lA ymknk t$gyl AltlfAz HtY tqlE AlTA}rp Ref: sorry you cannot turn the tv on until the plane has taken off 1-best: excuse me i you turn tv until the plane departs The phrase lA ymknk (you may not/you cannot) is translated differently (and wrongly in the second case) due to different segmentations and phrase translations chosen by the decoder.
the parameter values were 0.5 for the gap penalty, a maximum substring length of k = 4, and weights of 0, 0.1, 0.2, 0.7.