ABSTRACT. In type-theoretical semantics, sentences may often be interpreted as judgements, rather than propositions. When interpreting composite sentences such as those involving negations and conditionals, one may want to turn a judgemental interpretation into a proposition in order to obtain an intended semantics. In this paper, we propose a new negation operator $\NOT$ for constructing propositional forms of judgemental interpretations. NOT is introduced axiomatically, with five axiomatised laws to govern its behaviour, and several examples are given to illustrate its use in semantic interpretation. In order to justify NOT, we employ a heterogeneous equality to prove its laws and, since the addition of heterogeneous equality to type theories is consistent, so is our introduction of the NOT operator. Also discussed is how to use the negation operator in event semantics.

ABSTRACT. This note discusses work on lexical resources for Portuguese centered around OpenWordNet-PT, an open source wordnet-like resource for Portuguese. We discuss the initial developments, the sister project Nomlex-PT and mostly the applications that were developed in the quest for being able to do reasoning with Portuguese texts.

ABSTRACT. This paper compares three semantic parsing representations in their analysis of a few simple but central phenomena. These are PropS, AMR, and GKR for the representations, and passivization, coordination, and negation for the phenomena.

ABSTRACT. See attachment.

ABSTRACT. We present a method for finding errors in formalized natural language grammars, by automatically and systematically generating test cases that are intended to be judged by a human oracle. The method works on a per-construction basis; given a construction from the grammar, it generates a finite but complete set of test sentences (typically tens or hundreds), where that construction is used in all possible ways. Our method is an alternative to using a corpus or a treebank, where no such completeness guarantees can be made. The method is language-independent and is implemented for the grammar formalism \pmcfg{}, but also works for weaker grammar formalisms. We evaluate the method on a number of different grammars for different natural languages, with sizes ranging from toy examples to real-world grammars.

ABSTRACT. Anti-unification is a well-known method to compute generalizations in logic. Given two objects, the goal of anti-unification is to reflect commonalities between these objects in the computed generalizations, and highlight differences between them.

Anti-unification appears to be useful for various tasks in natural language processing. Semantic classification of sentences based on their syntactic parse trees, grounded language learning, semantic text similarity, insight grammar learning, metaphor modeling: This is an incomplete list of topics where generalization computation has been used in one form or another. The major anti-unification technique in these applications is the original method for first-order terms over fixed arity alphabets, introduced by Plotkin and Reynolds in 1970s, and some of its adaptations.

The goal of this paper is to give a brief overview about existing linguistic applications of anti-unification, discuss a couple of powerful and flexible generalization computation algorithms developed recently, and argue about their potential use in natural language processing tasks.

ABSTRACT. This paper contributes to symbolic inference from text, including naturally occurring text. The idea is to take sentences in a framework like CCG, and then run a polarizing algorithm like the one in Hu and Moss 2018 to determine inferential polarity markings of all the constituents. From this, it is just a small step to obtain an inference engine which is both simple to describe and implement and at the same time is suprisingly powerful. We have implemented the basic inference step. This paper is work in progress, also going into detail on our projected next steps. The overall goal is to have a working symbolic inference system which covers ``in-practice'' inference and also is correct and efficient.

ABSTRACT. This paper proposes an analysis of paycheck sentences in the framework of Dependent Type Semantics. We account for the anaphora resolution of paycheck pronouns by using dependent function types in dependent type theory. We argue that the presupposition of the possessive NP provides a function that contributes to the paycheck reading. The proposed analysis provides a uniform treatment of paycheck pronouns and standard referential pronouns, without introducing additional formal mechanisms to the system.

ABSTRACT. A natural question in categorial grammar is the relation between a syntactic analysis s and the logical form, i.e. the logical formula obtained from this syntactic analysis, once provided with semantic lambda terms. More precisely, do different syntactic analyses fed with equal semantic terms, lead to equal logical form? We shall show that when this question is too simply formulated, the answer is "NO" while with some constraints on semantic lambda terms the answer is "yes".