OPTIM and RANK require the setting of several parameters: (k, k , α, β) for OPTIM and (k, k , γ) for RANK.
taking into consideration the conditions mentioned the sentiment-inference problem can be formulated as an optimisation problem: After the substitutions α = ak + bk and β = b a the final optimisation problem can be written as: where β defines the relative weight between labeled and unlabeled neighbours, while α controls the weight of the graph-based solution with respect to the primarily obtained supervised sentiment scores.