Normalized compression distance based measures for metricsmatr 2010

We present the MT-NCD and MT-mNCD machine translation evaluation metrics as submission to the machine transla-tion evaluation shared task (MetricsMATR 2010). The metrics are based on nor-malized compression distance (NCD), a general information theoretic measure of string similarity, and evaluated against hu-man judgments from the WMT08 shared task. The experiments show that 1) our metric improves correlation to hu-man judgments by using flexible match-ing, 2) segment replication is effective, and 3) our NCD-inspired method for mul-tiple references indicates improved results. Generally, the proposed MT-NCD and MT-mNCD methods correlate competi-tively with human judgments compared to commonly used machine translations eval-uation metrics, for instance, BLEU.