On Certain Greedoid Polyhedra, Partially Indexable Scheduling Problems, and Extended Restless Bandit Allocation Indices

We present a polyhedral framework for establishing general structural properties on optimal solutions of stochastic scheduling problems, where multiple job classes vie for service resources: the existence of an optimal priority policy in a given family, characterized by a greedoid (whose feasible class subsets may receive higher priority), where optimal priorities are determined by class-ranking indices, under restricted linear performance objectives (partial indexability). This framework extends that of Bertsimas and Niño-Mora (1996), which explained the optimality of priority-index policies under all linear objectives (general indexability). We show that, if performance measures satisfy partial conservation laws (with respect to the greedoid), which extend previous generalized conservation laws, then the problem admits a strong LP relaxation over a so-called extended greedoid polytope, which has strong structural and algorithmic properties. We present an adaptive-greedy algorithm (which extends Klimov's) taking as input the linear objective coefficients, which (1) determines whether the optimal LP solution is achievable by a policy in the given family; and (2) if so, computes a set of class-ranking indices that characterize optimal priority policies in the family. In the special case of project scheduling, we show that, under additional conditions, the optimal indices can be computed separately for each project (index decomposition). We further apply the framework to the important restless bandit model (two-action Markov decision chains), obtaining new index policies, that extend Whittle's (1988), and simple sufficient conditions for their validity. These results highlight the power of polyhedral methods (the so-called achievable region approach) in dynamic and stochastic optimization.

Money, Fame and the Allocation of Talent: Brain Drain, the Matthew Effect and the Institution of Science

The earning structure in science is known to be flat relative to the one in the private sector, which could cause a brain drain toward the private sector. In this paper, we assume that agents value both money and fame and study the role of the institution of science in the allocation of talent between the science sector and the private sector. Following works on the Sociology of Science, we model the institution of science as a mechanism distributing fame (i.e. peer recognition). We show that since the intrinsic performance is less noisy signal of talent in the science sector than in the private sector, a good institution of science can mitigate the brain drain. We also find that providing extra monetary incentives through the market might undermine the incentives provided by the institution and thereby worsen the brain drain. Finally, we study the optimal balance between monetary and non-monetary incentives in science.

Financial Markets and Real Ecinomy: Four Essays in International Trade

Financial markets play an important role in an economy performing various functions like mobilizing and pooling savings, producing information about investment opportunities, screening and monitoring investments, implementation of corporate governance, diversification and management of risk. These functions influence saving rates, investment decisions, technological innovation and, therefore, have important implications for welfare. In my PhD dissertation I examine the interplay of financial and product markets by looking at different channels through which financial markets may influence an economy.My dissertation consists of four chapters. The first chapter is a co-authored work with Martin Strieborny, a PhD student from the University of Lausanne. The second chapter is a co-authored work with Melise Jaud, a PhD student from the Paris School of Economics. The third chapter is co-authored with both Melise Jaud and Martin Strieborny. The last chapter of my PhD dissertation is a single author paper.Chapter 1 of my PhD thesis analyzes the effect of financial development on growth of contract intensive industries. These industries intensively use intermediate inputs that neither can be sold on organized exchange, nor are reference-priced (Levchenko, 2007; Nunn, 2007). A typical example of a contract intensive industry would be an industry where an upstream supplier has to make investments in order to customize a product for needs of a downstream buyer. After the investment is made and the product is adjusted, the buyer may refuse to meet a commitment and trigger ex post renegotiation. Since the product is customized to the buyer's needs, the supplier cannot sell the product to a different buyer at the original price. This is referred in the literature as the holdup problem. As a consequence, the individually rational suppliers will underinvest into relationship-specific assets, hurting the downstream firms with negative consequences for aggregate growth. The standard way to mitigate the hold up problem is to write a binding contract and to rely on the legal enforcement by the state. However, even the most effective contract enforcement might fail to protect the supplier in tough times when the buyer lacks a reliable source of external financing. This suggests the potential role of financial intermediaries, banks in particular, in mitigating the incomplete contract problem. First, financial products like letters of credit and letters of guarantee can substantially decrease a risk and transaction costs of parties. Second, a bank loan can serve as a signal about a buyer's true financial situation, an upstream firm will be more willing undertake relationship-specific investment knowing that the business partner is creditworthy and will abstain from myopic behavior (Fama, 1985; von Thadden, 1995). Therefore, a well-developed financial (especially banking) system should disproportionately benefit contract intensive industries.The empirical test confirms this hypothesis. Indeed, contract intensive industries seem to grow faster in countries with a well developed financial system. Furthermore, this effect comes from a more developed banking sector rather than from a deeper stock market. These results are reaffirmed examining the effect of US bank deregulation on the growth of contract intensive industries in different states. Beyond an overall pro-growth effect, the bank deregulation seems to disproportionately benefit the industries requiring relationship-specific investments from their suppliers.Chapter 2 of my PhD focuses on the role of the financial sector in promoting exports of developing countries. In particular, it investigates how credit constraints affect the ability of firms operating in agri-food sectors of developing countries to keep exporting to foreign markets.Trade in high-value agri-food products from developing countries has expanded enormously over the last two decades offering opportunities for development. However, trade in agri-food is governed by a growing array of standards. Sanitary and Phytosanitary standards (SPS) and technical regulations impose additional sunk, fixed and operating costs along the firms' export life. Such costs may be detrimental to firms' survival, "pricing out" producers that cannot comply. The existence of these costs suggests a potential role of credit constraints in shaping the duration of trade relationships on foreign markets. A well-developed financial system provides the funds to exporters necessary to adjust production processes in order to meet quality and quantity requirements in foreign markets and to maintain long-standing trade relationships. The products with higher needs for financing should benefit the most from a well functioning financial system. This differential effect calls for a difference-in-difference approach initially proposed by Rajan and Zingales (1998). As a proxy for demand for financing of agri-food products, the sanitary risk index developed by Jaud et al. (2009) is used. The empirical literature on standards and norms show high costs of compliance, both variable and fixed, for high-value food products (Garcia-Martinez and Poole, 2004; Maskus et al., 2005). The sanitary risk index reflects the propensity of products to fail health and safety controls on the European Union (EU) market. Given the high costs of compliance, the sanitary risk index captures the demand for external financing to comply with such regulations.The prediction is empirically tested examining the export survival of different agri-food products from firms operating in Ghana, Mali, Malawi, Senegal and Tanzania. The results suggest that agri-food products that require more financing to keep up with food safety regulation of the destination market, indeed sustain longer in foreign market, when they are exported from countries with better developed financial markets.Chapter 3 analyzes the link between financial markets and efficiency of resource allocation in an economy. Producing and exporting products inconsistent with a country's factor endowments constitutes a serious misallocation of funds, which undermines competitiveness of the economy and inhibits its long term growth. In this chapter, inefficient exporting patterns are analyzed through the lens of the agency theories from the corporate finance literature. Managers may pursue projects with negative net present values because their perquisites or even their job might depend on them. Exporting activities are particularly prone to this problem. Business related to foreign markets involves both high levels of additional spending and strong incentives for managers to overinvest. Rational managers might have incentives to push for exports that use country's scarce factors which is suboptimal from a social point of view. Export subsidies might further skew the incentives towards inefficient exporting. Management can divert the export subsidies into investments promoting inefficient exporting.Corporate finance literature stresses the disciplining role of outside debt in counteracting the internal pressures to divert such "free cash flow" into unprofitable investments. Managers can lose both their reputation and the control of "their" firm if the unpaid external debt triggers a bankruptcy procedure. The threat of possible failure to satisfy debt service payments pushes the managers toward an efficient use of available resources (Jensen, 1986; Stulz, 1990; Hart and Moore, 1995). The main sources of debt financing in the most countries are banks. The disciplining role of banks might be especially important in the countries suffering from insufficient judicial quality. Banks, in pursuing their rights, rely on comparatively simple legal interventions that can be implemented even by mediocre courts. In addition to their disciplining role, banks can promote efficient exporting patterns in a more direct way by relaxing credit constraints of producers, through screening, identifying and investing in the most profitable investment projects. Therefore, a well-developed domestic financial system, and particular banking system, would help to push a country's exports towards products congruent with its comparative advantage.This prediction is tested looking at the survival of different product categories exported to US market. Products are identified according to the Euclidian distance between their revealed factor intensity and the country's factor endowments. The results suggest that products suffering from a comparative disadvantage (labour-intensive products from capital-abundant countries) survive less on the competitive US market. This pattern is stronger if the exporting country has a well-developed banking system. Thus, a strong banking sector promotes exports consistent with a country comparative advantage.Chapter 4 of my PhD thesis further examines the role of financial markets in fostering efficient resource allocation in an economy. In particular, the allocative efficiency hypothesis is investigated in the context of equity market liberalization.Many empirical studies document a positive and significant effect of financial liberalization on growth (Levchenko et al. 2009; Quinn and Toyoda 2009; Bekaert et al., 2005). However, the decrease in the cost of capital and the associated growth in investment appears rather modest in comparison to the large GDP growth effect (Bekaert and Harvey, 2005; Henry, 2000, 2003). Therefore, financial liberalization may have a positive impact on growth through its effect on the allocation of funds across firms and sectors.Free access to international capital markets allows the largest and most profitable domestic firms to borrow funds in foreign markets (Rajan and Zingales, 2003). As domestic banks loose some of their best clients, they reoptimize their lending practices seeking new clients among small and younger industrial firms. These firms are likely to be more risky than large and established companies. Screening of customers becomes prevalent as the return to screening rises. Banks, ceteris paribus, tend to focus on firms operating in comparative-advantage sectors because they are better risks. Firms in comparative-disadvantage sectors finding it harder to finance their entry into or survival in export markets either exit or refrain from entering export markets. On aggregate, one should therefore expect to see less entry, more exit, and shorter survival on export markets in those sectors after financial liberalization.The paper investigates the effect of financial liberalization on a country's export pattern by comparing the dynamics of entry and exit of different products in a country export portfolio before and after financial liberalization.The results suggest that products that lie far from the country's comparative advantage set tend to disappear relatively faster from the country's export portfolio following the liberalization of financial markets. In other words, financial liberalization tends to rebalance the composition of a country's export portfolio towards the products that intensively use the economy's abundant factors.

Adjustment to Target Capital, Finance, and Growth

Does financial development result in capital being reallocated more rapidly to industries where it is most productive? We argue that if this was the case, financially developed countries should see faster growth in industries with investment opportunities due to global demand and productivity shifts. Testing this cross-industry cross-country growth implication requires proxies for (latent) global industry investment opportunities. We show that tests relying only on data from specific (benchmark) countries may yield spurious evidence for or against the hypothesis. We therefore develop an alternative approach that combines benchmark-country proxies with a proxy that does not reflect opportunities specific to a country or level of financial development. Our empirical results yield clear support for the capital reallocation hypothesis.

Capital Social e Expectativas de Carreira de Estudantes de Ascendência Africana

Segundo a literatura, as condições sociais e culturais exercem grandes influências no processo de escolha de carreira. Por outro lado, o capital social pode ser um excelente recurso para conseguir boas oportunidades de emprego no mercado de trabalho. A presente investigação procura estudar o impacto dos antecedentes sociais e do capital social sob as expectativas de carreira de jovens universitários de ascendência africana. A recolha dos dados foi feita através da aplicação de um questionário a vários alunos do ensino superior de várias universidades portuguesas (públicas e privadas), a fim de medir as seguintes variáveis: a auto-eficácia escolar, a instrumentalidade escolar, o locus de controlo, a instrumentalidade no trabalho, a expectativa face ao trabalho, e o capital social. A amostra é constituída por 150 estudantes, 82 do sexo feminino e 66 do sexo masculino, com idades compreendidas entre os 19 e os 44 anos, e 102 estudantes com pais de nacionalidade portuguesa e 45 com pais de nacionalidade africana. Mostram os resultados do presente estudo que a pertença a uma rede social com bons recursos e prestadora de apoio faz desenvolver menos expectativas de dimensões extrínsecas nos estudantes no início de carreira. Ainda, de acordo com os resultados, sabe-se que os estudantes universitários de ascendência africana desenvolvem atitudes mais positivas face à escola e desenvolvem mais expectativas de dimensões extrínsecas face ao trabalho.

Iowa Budget Report Capital Projects, January 2005

This report is of the projects for the capital.

A política de formação de quadros e o capital cultural dos altos funcionários públicos cabo-verdianos

A estratégia de desenvolvimento de Cabo Verde tem passado por um acentuado investimento na formação dos seus recursos humanos, desde a expansão e democratização do ensino básico até à recente criação da Universidade estatal. A aposta numa política de formação de quadros teve de contar com a cooperação com outros países, dada a inexistência de ensino superior nas ilhas e à incapacidade financeira para a sua implementação. Nesta apresentação, pretende-se demonstrar que uma das consequências do investimento na educação foi a constituição de uma elite cujo traço comum é a sua formação académica adquirida fora das ilhas e a capacidade técnica desenvolvida na chefia dos serviços públicos. Desse capital cultural faz parte toda a experiência que conseguiram amealhar no estrangeiro durante o seu período de estudos universitários, debatendo-se com obstáculos linguísticos, culturais, financeiros e, até, identitários, os quais representam uma riqueza adicional ao seu perfil enquanto dirigentes da administração pública cabo-verdiana.

A CONTABILIDADE E O REAL VALOR DAS EMPRESAS: FOCO NO CAPITAL INTELECTUAL

Este trabalho mostra que a contabilidade pode não estar a evidenciar o real valor do património das empresas (um dos seus objectivos), constatamos nos últimos tempos, que os relatórios fornecidos pela contabilidade financeira não retratam certas realidades das empresas, visto que o valor contabilístico se distancia cada vez mais do valor de mercado, principalmente nas empresas de alta tecnologia e serviços, assim sendo as demonstrações financeiras podem estar experimentando uma perda de relevância para a tomada de decisões de investimentos, de crédito e de gestão. Dentro deste contexto, ressaltamos a necessidade de a contabilidade evidenciar naquelas demonstrações tais informações para que possa divulgar aos vários utentes da informação o real valor da empresa. Visto que o Capital Intelectual é importante para as empresas, torna-se necessário relatar não só informações financeiras como também não financeiras. Este trabalho apresenta um estudo descritivo/quantitativo da empresa CVTelecom, com o objectivo de avaliar o grau de divulgação do Capital Intelectual na empresa. A principal constatação foi o seguinte: uma participação activa da empresa em divulgar o Capital Intelectual, uma forma não normalizada através da divulgação voluntária do Capital Intelectual cujo veículo de divulgação, é o Relatório de Gestão e o Balanço Social. This work shows that the Accounting cannot be evidencing the Real value of the patrimony of the enterprises (one of their objectives), we verified in the last times, that the reports supplied by the Financial Accounting don't portray certain realities of the enterprises, because the value Accounting of the enterprises go away more and more of his market value, mainly in the companies of high technology and services, soon the financial demonstrations are trying a loss of relevance for socket of decisions of investments, of credit and of administration. Inside of this context, we emphasized the need of the Accounting to evidence in the demonstrations such financial information so that it can publish to the several users of the information the Real value of the company. Because the Intellectual Capital is important for the enterprises, it becomes necessary to tell not only financial information as well as any financial. This work presents a descriptive-quantitative study of the enterprise CVtelecom, with the objective of evaluating the degree of popularization of the Intellectual Capital in the enterprise and the impact in the performance of this enterprise. The main verification was the following: A participation active of the company in publishing the Intellectual Capital in spite of being in a way no normalized but a voluntary popularization of the Intellectual Capital, whose popularization vehicle is the Report of Administration and the Social Swinging.

Capital Social e Políticas Públicas: Análise da implementação do Programa de Luta Contra a Pobreza no Meio Rural nos municípios de São Miguel e Tarrafal

Este trabalho foi desenvolvido no quadro da realização do Mestrado em Ciências Sociais pela Universidade de Cabo Verde. Tem como objectivo analisar as possibilidades e os limites de concretização da estratégia de redução da pobreza adoptada pelo Programa de Luta Contra a Pobreza no Meio Rural que considera o capital social como recurso para o desenvolvimento das comunidades. Em específico, procura analisar como essa estratégia é apropriada e implementada pelas associações comunitárias de desenvolvimento e o impacto das actividades desenvolvidas por essas associações no capital social e na redução da pobreza nos municípios de São Miguel e Tarrafal na ilha de Santiago. A recolha de dados foi feita, basicamente, junto de líderes de associações comunitárias de desenvolvimento e de chefes de agregados familiares, com base num guião de entrevista e num questionário previamente elaborados. Em termos teóricos, a concepção de capital social formulada por Robert Putnam constitui o eixo analítico do presente trabalho. Os dados recolhidos apontam que para além dos inquiridos não assumirem a ideia de comunidade preconizada pelo Programa de Luta Contra a Pobreza no Meio Rural, que as actividades desenvolvidas pelas associações comunitárias de desenvolvimento não contribuíram para um reforço significativo do capital social das comunidades abrangidas pelo estudo, não obstante reconhecerem que essas actividades tiveram um impacto positivo na redução da pobreza.

PhD Students’ Research Group Social Capital in Two Countries: A Clustering Approach with Duocentred Network Measures

The article examines the structure of the collaboration networks of research groups where Slovenian and Spanish PhD students are pursuing their doctorate. The units of analysis are student-supervisor dyads. We use duocentred networks, a novel network structure appropriate for networks which are centred around a dyad. A cluster analysis reveals three typical clusters of research groups. Those which are large and belong to several institutions are labelled under a bridging social capital label. Those which are small, centred in a single institution but have high cohesion are labelled as bonding social capital. Those which are small and with low cohesion are called weak social capital groups. Academic performance of both PhD students and supervisors are highest in bridging groups and lowest in weak groups. Other variables are also found to differ according to the type of research group. At the end, some recommendations regarding academic and research policy are drawn

Capital de Risco- Uma alternativa de Financiamento: Caso Cabo Verde

Este estudo procura conhecer/testar se o Capital de risco é de facto uma alternativa viável de financiamento e conhecer o percurso e o impacto da actividade de capital de risco em Cabo Verde. Para este efeito, foi feito uma revisão bibliográfica relacionada com a matéria, e, para o caso de Cabo Verde, foi feito uma recolha de opiniões junto da única sociedade de CR no país, junto de técnicos dos Bancos comerciais da praça, da Câmara de Comércio de Sotavento e das participadas de A PROMOTORA, SA.

The capital gains from trade are not enough: Evidence from the environmental accounts of Venezuela and Mexico

In principle, a country can not endure negative genuine savings for longperiods of time without experiencing declining consumption. Nevertheless,theoreticians envisage two alternatives to explain how an exporter ofnon-renewable natural resources could experience permanent negativegenuine savings and still ensure sustainability. The first one allegesthat the capital gains arising from the expected improvement in theterms of trade would suffice to compensate for the negative savings ofthe resource exporter. The second alternative points at technologicalchange as a way to avoid economic collapse. This paper uses the dataof Venezuela and Mexico to empirically test the first of these twohypotheses. The results presented here prove that the terms oftrade do not suffice to compensate the depletion of oil reservesin these two open economies.

Capital, wages and growth: Theory and evidence

Returns to scale to capital and the strength of capital externalities play a key role for the empirical predictions and policy implications of different growth theories. We show that both can be identified with individual wage data and implement our approach at the city-level using US Census data on individuals in 173 cities for 1970, 1980, and 1990. Estimation takes into account fixed effects, endogeneity of capital accumulation, and measurement error. We find no evidence for human or physical capital externalities and decreasing aggregate returns to capital. Returns to scale to physical and human capital are around 80 percent. We also find strong complementarities between human capital and labor and substantial total employment externalities.