In our research, 23 scores, namely BLEU (Papineni et al., 2002) with maximum n-gram lengths of 1, 2, 3, and 4, NIST (NIST, 2002) with maximum n-gram lengths of 1, 2, 3, 4, and 5, GTM (Turian et al., 2003) with exponents of 1.0, 2.0, and 3.0, METEOR (exact) (Banerjee and Lavie, 2005), WER (Niessen et al., 2000), PER (Leusch et al., 2003), and ROUGE (Lin, 2004) with n-gram lengths of 1, 2, 3, and 4 and 4 variants (LCS, S * , SU * , W-1.2), were used to calculate each similarity S i .
the value of m in Eq.