La actualidad de la deuda argentina. Resolución del default, actores y políticas en el modelo post-convertibilidad, 2002-2007

Fil: Varesi, Gastón Angel. Universidad Nacional de La Plata. Facultad de Humanidades y Ciencias de la Educación; Argentina.

La actualidad de la deuda argentina. Resolución del default, actores y políticas en el modelo post-convertibilidad, 2002-2007

Fil: Varesi, Gastón Angel. Universidad Nacional de La Plata. Facultad de Humanidades y Ciencias de la Educación; Argentina.

The pragmatic motifs of the Jespersen cycle: default, activation, and the history of negation in French

The purpose of this article is to delimit the role of pragmatic specialization in the evolution of negation in French. The change in the marking of sentential negation is believed to proceed in characterized stages that would together constitute the Jespersen cycle. As a marker becomes the default expression of negation, the other markers do not necessarily fade away, and are maintained with specialized roles that include pragmatic functions. One such pragmatic function is that of activation (Dryer 1996), by which a proposition is presented as accessible to the hearer. Activation is shown to motivate the use of preverbal non that competes with 'ne' for several centuries. The claims that the emergence of postverbal pas in early French and the loss of 'ne' in contemporary spoken French are associated with activation are considered on the basis of novel data. It is concluded that pragmatic functions contribute to language change by providing marked options that may be conferred the default status in a grammatical paradigm.

Representing "Recursive" Default Logic in Modal Logic

The "recursive" definition of Default Logic is shown to be representable in a monotonic Modal Quantificational Logic whose modal laws are stronger than S5. Specifically, it is proven that a set of sentences of First Order Logic is a fixed-point of the "recursive" fixed-point equation of Default Logic with an initial set of axioms and defaults if and only if the meaning of the fixed-point is logically equivalent to a particular modal functor of the meanings of that initial set of sentences and of the sentences in those defaults. This is important because the modal representation allows the use of powerful automatic deduction systems for Modal Logic and because unlike the original "recursive" definition of Default Logic, it is easily generalized to the case where quantified variables may be shared across the scope of the components of the defaults.

Representing Default Logic in Modal Logic

The nonmonotonic logic called Default Logic is shown to be representable in a monotonic Modal Quantificational Logic whose modal laws are stronger than S5. Specifically, it is proven that a set of sentences of First Order Logic is a fixed-point of the fixed-point equation of Default Logic with an initial set of axioms and defaults if and only if the meaning or rather disquotation of that set of sentences is logically equivalent to a particular modal functor of the meanings of that initial set of sentences and of the sentences in those defaults. This result is important because the modal representation allows the use of powerful automatic deduction systems for Modal Logic and because unlike the original Default Logic, it is easily generalized to the case where quantified variables may be shared across the scope of the components of the defaults thus allowing such defaults to produce quantified consequences. Furthermore, this generalization properly treats such quantifiers since both the Barcan Formula and its converse hold.

On the Relationship between Quantified Reflective Logic and Quantified Default Logic

Reflective Logic and Default Logic are both generalized so as to allow universally quantified variables to cross modal scopes whereby the Barcan formula and its converse hold. This is done by representing both the fixed-point equation for Reflective Logic and the fixed-point equation for Default both as necessary equivalences in the Modal Quantificational Logic Z. and then inserting universal quantifiers before the defaults. The two resulting systems, called Quantified Reflective Logic and Quantified Default Logic, are then compared by deriving metatheorems of Z that express their relationships. The main result is to show that every solution to the equivalence for Quantified Default Logic is a strongly grounded solution to the equivalence for Quantified Reflective Logic. It is further shown that Quantified Reflective Logic and Quantified Default Logic have exactly the same solutions when no default has an entailment condition.

Dividend increases and initiations and default risk in equity returns

This study extends the Grullon, Michaely, and Swaminathan (2002) analysis by incorporating default risk. Using data for firms that either increased or initiated cash dividend payments during the 23-year period 1986-2008, we find reduction in default risk. This reduction is shown to be a priced risk factor beyond the Fama and French (1993) risk measures, and it explains the dividend payment decision and the positive market reaction around dividend increases and initiations. Further analysis reveals that the reduction in default risk is a significant factor in explaining the 3-year excess returns following dividend increases and initiations. © Copyright Michael G. Foster School of Business, University of Washington 2011.

'Digital by Default' and the 'hard to reach' : exploring solutions to digital exclusion in remote rural areas

The research reported here is supported by the award made by the RCUK Digital Economy programme to the dot.rural Digital Economy Hub [award reference: EP/G066051/1].

Explanation, Dialogue and Default Logic

La distinción entre argumentación y explicación es una tarea complicada pero necesaria por diversas razones. Una de ellas es la necesidad de incorporar la explicación en un movimiento del diálogo como resultado de una obligación dialéctica. Se propusieron distintos sistemas de diálogo que exploran la distinción enfatizando aspectos pragmáticos. En el presente trabajo me ocupo de aspectos estructurales de la explicación analizados en el marco de la lógica por defecto que permite caracterizar ciertas objeciones en el diálogo. Asimismo, considero que la versión operacional de la lógica por defecto constituye una aproximaciónadecuada en la construcción de la explicación y en la representación de la instancia de diálogo en el intercambio dialéctico

Default Invariance: Naïve Category of Law and Finance

Default invariance is the idea that default does not change at any scale of law and finance. Default is a conserved quantity in a universe where fundamental principles of law and finance operate. It exists at the micro-level as part of the fundamental structure of every financial transaction, and at the macro- level, as a fixed critical point within the relatively stable phases of the law and finance cycle. A key point is that default is equivalent to maximizing uncertainty at the micro-level and at the macro-level, is equivalent to the phase transition where unbearable fluctuations occur in all forms of risk transformation, including maturity, liquidity and credit. As such, default invariance is the glue that links the micro and macro structures of law and finance. In this essay, we apply naïve category theory (NCT), a type of mapping logic, to these types of phenomena. The purpose of using NCT is to introduce a rigorous (but simple) mathematical methodology to law and finance discourse and to show that these types of structural considerations are of prime practical importance and significance to law and finance practitioners. These mappings imply a number of novel areas of investigation. From the micro- structure, three macro-approximations are implied. These approximations form the core analytical framework which we will use to examine the phenomena and hypothesize rules governing law and finance. Our observations from these approximations are grouped into five findings. While the entirety of the five findings can be encapsulated by the three approximations, since the intended audience of this paper is the non-specialist in law, finance and category theory, for ease of access we will illustrate the use of the mappings with relatively common concepts drawn from law and finance, focusing especially on financial contracts, derivatives, Shadow Banking, credit rating agencies and credit crises.