International Fragmentation of Production in the Portuguese Economy: What do Different Measures Tell Us?

This paper analyses the relevance and the characteristics of the international fragmentation of production in the Portuguese economy. The empirical trade literature suggests different measures of fragmentation, changing the scope of the concept and using alternative sets of information. The existing measures can be broadly divided in those that make use of Input-Output matrices together with international trade data and those that look at specific elements of international transactions, namely trade in parts and components and outward-inward processing trade. In this paper, we survey the different measures of international fragmentation of production and apply them to Portuguese data. Our results of Input-Output based measures point to a substantial increase of the vertical linkages in the Portuguese economy, in particular since the nineties. Nevertheless, it seems that the pace of vertical specialization has been somewhat modest in international terms. The share of exports of parts and components in total trade has almost doubled in the last two decades, while the import share of these goods has remained nearly stable. Processing trade represents a very low share of Portuguese international trade.

Vertical Specialization Across the World: A Relative Measure

This paper investigates a specific aspect of international production linkages that, following Hummels et al. (2001), is commonly designated as vertical specialization (VS) - the use of imported inputs to produce goods that are afterwards exported. We propose a relative measure of VS-based trade that combines information from Input-Output matrices and international trade data, producing results for a large sample of individual countries and geographical areas with a detailed product breakdown over the 1967-2005 period. This measure identifies a country’s trade flow as associated with VS activities when the share of exports of a good relatively to the world average is above a given threshold and it is accompanied by a relative share of imports of a related intermediate product that is also above the threshold. The quantification of VS-based trade for each country/product pair in each period is made in a relative and conservative manner, since it includes only the value of intermediate imports that surpasses what is implied by the chosen international threshold. The detailed results can be subsequently added up to get any product or geographical breakdown desired. We illustrate this measure by showing the evolution of VS activities at the world level over the last four decades using a product breakdown by technological intensity and a geographical breakdown by main areas. The results point to a substantial increase of VS in high-technology products over the last two decades. There is also empirical evidence on the sharp increase of VS activities in East Asia.

Bank capital and equity investment regulations

An intermediation model that examines the efficiency and welfare implications of banks' required capital-asset ratio and of the regulations that limit - and in some countries forbid - banks' investments in equity to a certain proportion of each firm's capital. ; A look at how episodes of competing currencies can provide insight on 1) the qualities of a commodity that lead to its becoming a dominant currency, 2) the route by which a nationally mandated paper currency becomes acceptable as a medium of exchange, and 3) the way in which competition between currencies sustains the exchange value of a fiat currency by restricting the actions available to the monetary authority. ; A look at how episodes of competing currencies can provide insight on 1) the qualities of a commodity that lead to its becoming a dominant currency, 2) the route by which a nationally mandated paper currency becomes acceptable as a medium of exchange, and 3) the way in which competition between currencies sustains the exchange value of a fiat currency by restricting the actions available to the monetary authority.Bank capital ; Bank investments

Debt and equity as optimal contracts

Using a principal-agent model in which an entrepreneur has an investment project whose returns depend on his effort, which is not observable by the financier, the author shows that the optimal contract used to finance such a project can be replicated by a unique combination of debt and equity, proving the optimality of these financial instruments. ; A look at the evolution of the collection, clearinghouse, and regulatory provisions of the Federal Reserve Act. The Reserve Banks’ check collection service was designed in 1913 to serve as "glue," attaching the new central bank to the commercial and financial markets through member banks.Contracts ; Corporations - Finance

Glimpses of Scientific Mathematic Modules in High School

This journal provides immediate open access to its content on the principle that making research freely available to the public supports a greater global exchange of knowledge.The introduction of advanced scientific modules to support teaching has an important fundamental in mathematics education. But this kind of introduction collides with the lack of time that the teachers of High School have to develop new strategies and implement them, because they are attached, in Portugal, to a bureaucratic machine that consumes valuable time that could be invested in education. Didactic concepts and scientific content must work together like a gear of knowledge. The didactic knowledge allows introducing concepts that are later explored scientifically enabling educational expansion, which will be reflected in the student's creativity. We assist to a dialectical progression knowledge, which will have immediate effects on motivation and capture the attention by those who learn, so in this work we present a model to introduce some advanced Scientific Modules from some graduations of University Mathematics curriculum in Portuguese High Schools

Symbolic Dynamics for Real Rational Maps

This work is an attempt to study the dynamics of real rational maps f ab (x) = (x 2 - a) / (x 2 - b), using symbolic dynamics. It is given an example that illustrates how the topological entropy can be calculated using kneading theory and Markov partitions in this family of rational maps

A Modelação Matemática e a simplificação da complexidade

A secção UAciência é coordenada pelo Professor Universitário Armindo Rodrigues.[…]. O modo como a teoria e as aplicações da Matemática se relacionam é designado por matematização ou modelação matemática. Isto significa que qualquer descrição matemática do mundo real é um modelo. Manipulando o modelo produzimos um estudo, do qual esperamos compreender algo da realidade, através da interpretação dos resultados obtidos. Como a sua construção tem de estar assente nos princípios sólidos da matemática, a forma como as estruturas são articuladas passa para plano secundário, sendo o mais importante a verificação experimental das suas implicações. […]. Como exemplo da sua utilidade vejamos o caso do Turismo na R.A. dos Açores. Uma área vital para o seu desenvolvimento, que possibilita o aproveitamento dos recursos naturais, culturais, gastronómicos, entre outros, geradores de riqueza local, contribuindo para a criação de postos de trabalho, incrementando os índices da felicidade e qualidade vida das populações. Devido a extrema complexidade da rede em que este assenta, torna-se impossível entender todas as inter-relações de uma só vez. Assim, há a necessidade de usar uma estrutura que seja analiticamente simplificada. […].info:eu-repo/semantics/publishedVersio