Hatzivassiloglou, V., & Wiebe, J.M. 2000. Effects of adjective orientation and gradability on sentence subjectivity. Proceedings of 18th International Conference on Computational Linguistics.
Thumbs Up or Thumbs Down? Semantic Orientation Applied to Unsupervised Classification of Reviews
That is, there is no grading assumed for a weak module. A weak V -module W is said to be N-gradable (cf. [Z]) if there exists an N-grading W = ⊕n∈NW (n) such that umW (n) ⊆ W (wtu − m − 1 + n) for homogeneous u ∈ V and for m ∈ Z, n ∈ N, where by deﬁnition W (k) = 0 for k < 0.
Certain generating subspaces for vertex operator algebras
Since Zhu’s C2 -ﬁniteness condition on V implies that dim A(V ) < ∞ ([Z], [DLM3]), by Zhu’s one-to-one correspondence V has only ﬁnitely many irreducible N-gradable weak V -modules up to equivalence and each of them has a ﬁnite-dimensional lowest weight subspace.
Certain generating subspaces for vertex operator algebras
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