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We explore the contribution of lexical and inflectional morphology features to dependency parsing of Arabic, a morphologically rich language with complex agreement patterns. Using controlled experiments, we contrast the contribution of different part-of-speech (POS) tag sets and morphological features in two input conditions: machine-predicted condition (in which POS tags and morphological feature values are automatically assigned), and gold condition (in which their true values are known). We find that more informative (fine-grained) tag sets are useful in the gold condition, but may be detrimental in the predicted condition, where they are outperformed by simpler but more accurately predicted tag sets. We identify a set of features (definiteness, person, number, gender, and undiacritized lemma) that improve parsing quality in the predicted condition, whereas other features are more useful in gold. We are the first to show that functional features for gender and number (e.g., "broken plurals"), and optionally the related rationality ("humanness") feature, are more helpful for parsing than form-based gender and number. We finally show that parsing quality in the predicted condition can dramatically improve by training in a combined gold+predicted condition. We experimented with two transition-based parsers, MaltParser and Easy-First Parser. Our findings are robust across parsers, models, and input conditions. This suggests that the contribution of the linguistic knowledge in the tag sets and features we identified goes beyond particular experimental settings, and may be informative for other parsers and morphologically rich languages. [ABSTRACT FROM AUTHOR]

The study of adjectival diathesis alternations lags behind the study of verbal diathesis and nominalization. This paper aims to diminish the gap by applying to the adjectival domain theoretical tools with proven success elsewhere. We focus on evaluative adjectives, which display a systematic alternation between a basic variant (John was rude) and a derived one (That was rude of John). The alternation brings about a cluster of syntactic and semantic changes - in the semantic type of the predicate, its valency and the mode of argument projection. We argue that the adjectival variants are related by the joint application of two operators: a lexical SATURATION operator (also seen in verbal passive) and a syntactic REIFICATION operator (also seen in nominalization). The analysis straightforwardly extends to similar alternations with Subject- and Object-Experiencer adjectives (proud, irritating). Among its important implications are (i) lexical saturation is not restricted to external arguments (internal ones may also be saturated), and (ii) ' referential ' (R) roles are not restricted to nominal predicates (adjectives may assign them as well). [ABSTRACT FROM AUTHOR]

This article addresses general questions about the organization of grammar via a detailed discussion of a small, but well-explored, area of English: the contraction of want to to wanna. It distinguishes three general approaches to the analysis of wanna: a phonological rule, lexicalization, or a derivational rule. Each approach has a different set of strengths, but they all have weaknesses as well. The article then offers a new analysis in terms of REALIZATION, which combines the strengths of all the previous analyses. This analysis, which is based on the theory of word grammar, accounts not only for all the well-known syntactic and morphological constraints on this contraction, but also for a fact that has not been noted before: that, for some speakers, the last vowel alternates in just the same idiosyncratic way as that of to, which suggests strongly that in some sense wanna contains to as well as want. For these (but not all) speakers, the proposed analysis recognizes two words (sublexemes of WANT and TOinf) at the level of syntax and a single form ({wanna}, containing variants of {want} and {to}) at the level of form; the relations between these words and forms, and between the forms and their phonological realizations, are defined by a declarative network. [ABSTRACT FROM AUTHOR]