If the entropy of probability distribution − K k=1 p L k logp L k > E 0 ( E 0 = 1.5 in this paper), we treat this word as an ambiguous word.
the sentences containing troublesome words can be divided into four different parts: 1) sentences which contain both lowfrequency and ambiguous words (Low+Amb, Rectify Deterio Arthur(test) 51 17 Baseline+MEM 70 11 Table 5: The numbers of rectification (Rectify) and deterioration (Deterio) caused by different models.