ROUGE-L stands for recall-oriented understudy for gisting evaluation with the longest common subse-
quence. Given the candidate C and reference R, let LCS(C, R) be the length of the longest common
subsequence, which is determined by using dynamic programming, it can be an expression as:

ROUGE-L = (1 + β2)RLCSPLCS
RLCS + β2PLCS

,

(1)

where RLCS = LCS(C,R)
reference.

c

, PLCS = LCS(C,R)

r

, β = PLCS
RLCS

. c and r represent the length of the candidate and

METEOR stands for metric for evaluation of translation with explicit ordering. We represent precision
r and let m be the number of common words in the candidate C and the
and recall as P = m
reference R with the number of words of c and r, respectively. The METEOR is calculated via

c and R = m

where p is the penalty factor and is denoted as p = γ( ch
contiguous ordered block. α, θ, γ are hyperparameters determined according to different datasets.

METEOR = (1 − p) ×

P R

,
BiomedGPT