arXiv subjects

Santiago Figueira

Publications and source records attributed to Santiago Figueira.

20 records · Page 2Linked to original sources

arXiv2011

Ackermannian and Primitive-Recursive Bounds with Dickson's Lemma

Dickson's Lemma is a simple yet powerful tool widely used in termination proofs, especially when dealing with counters or related data structures. However, most computer scientists do not know how to derive complexity upper bounds from such termination proofs, and the existing literature is not very helpful in these matters. We propose a new analysis of the length of bad sequences over (N^k,\leq) and explain how one may derive complexity upper bounds from termination proofs. Our upper bounds improve earlier results and are essentially tight.

cs.LO↗

arXiv2010

The Question of Expressiveness in the Generation of Referring Expressions

We study the problem of generating referring expressions modulo different notions of expressive power. We define the notion of $\+L$-referring expression, for a formal language $\+L$ equipped with a semantics in terms of relational models. We show that the approach is independent of the particular algorithm used to generate the referring expression by providing examples using the frameworks of \cite{AKS08} and \cite{Krahmer2003}. We provide some new complexity bounds, discuss the issue of the length of the generated descriptions, and propose ways in which the two approaches can be combined.

cs.LO↗