Z λ (x) = ỹ∈Y c∈C(ỹ,x) Φ c (ỹ, x; λ) is a normalization factor over all output values, Y.
following the definitions of (Sha and Pereira, 2003), a log-linear combination of weighted features, Φ c (y, x; λ) = exp(λ • f c (y, x)), is used as individual potential functions, where f c represents a feature vector obtained from the corresponding clique c. is the CRf's global feature vector for x and y.