We show that the expressive power of first-order logic over finite models embedded in a model M is determined by stability-theoretic properties of M . In particular, we show that if M is stable, then every class of finite structures that can be defined by embedding the structures in M , can be defined in pure first-order logic. We also show that if M does not have the independence property, the...

ions for Model-Checking Game-theoretic Properties in Combinatorial Auctions E.M. Tadjouddine F. Guerin W. Vasconcelos Univ. of Aberdeen, Dept. of Computing Science, Aberdeen AB24 3UE, UK [email protected], [email protected], [email protected]

In an earlier paper (MLQ 54, 128–144) the first author initiated the study of generic cuts of a model of Peano Arithmetic relative to a notion of an indicator in the model. This paper extends that work. We generalise the idea of indicator to a related neighbourhood system; this allows the theory to be extended to one that includes the case of elementary cuts. Most results transfer to this more ...

Given an unknown attractor A in a continuous dy-namical system, how we can discover the topology and dynamics of A? As a practical matter, how can we do so from only a nite amount of information? One way of doing so is to produce a semi-conjugacy from A onto a model system M whose topology and dynamics are known. The complexity of M then provides a lower bound for the complexity of A. The Conle...

In this paper we answer a question of Friedman, providing an !-separable model M of the-calculus. There therefore exists an-separable model for any 0. The model M permits no non-trivial enrichment as a partial order; neither does it permit an enrichment as a category with an initial object. The open term model embeds in M: by way of contrast we provide a model which cannot embed in any non-triv...

The purpose of this study is to examine the influence of overseas R&D on firm productivity. In particular, we further consider the moderating effect of internal technological capability. To provide more empirical evidence, this analysis takes advantage of a longitudinal dataset covering the 2009-2013 period and the system-GMM approach is employed in the empirical analysis to control for the pro...

Estimating the error of classification and regression models is one of the most crucial tasks in machine learning. While the global error is capable to measure the quality of a model, local error estimates are even more interesting: on the one hand they contribute to better understanding of prediction models (where does and where does not work the model well), on the other hand they may provide...

We present an algebraic Bethe ansatz for certain submanifolds of the bilayer vertex models proposed by Shiroishi and Wadati as coupled asymmetric six-vertex free-fermion models. A peculiar feature of our formulation is the presence of a diagonal monodromy matrix element that does not generate unwanted terms. The model contains two free-parameters entering into the Bethe ansatz equations as a pu...

Propositional logic formulas containing implications can suffer from antecedent failure, in which the formula is true trivially because the pre-condition of the implication is not satisfiable. In other words, the post-condition of the implication does not affect the truth value of the formula. We call this a vacuous pass, and extend the definition of vacuity to cover other kinds of trivial pass...

In seeking a unified study of computational effects, in particular in order to give a general operational semantics agreeing with the standard one for state, one must take account of the coalgebraic structure of state. Axiomatically, one needs a countable Lawvere theory L, a comodel C, typically the final one, and a model M , typically free; one then seeks a tensor C ⊗ M of the comodel with the...