Returns to vocational education in Portugal

A Work Project, presented as part of the requirements for the Award of a Masters Degree in Economics from the NOVA – School of Business and Economics

Bias in returns to tenure when firm wages and employment comove: A quantitative assessment and solution

It is well known that, unless worker-firm match quality is controlled for, returns to firm tenure (RTT) estimated directly via reduced form wage (Mincer) equations will be biased. In this paper we show that even if match quality is properly controlled for there is a further pervasive source of bias, namely the co-movement of firm employment and firm wages. In a simple mechanical model where human capital is absent and separation is exogenous we show that positively covarying shocks (either aggregate or firm level) to firms employment and wages cause downward bias in OLS regression estimates of RTT. We show that the long established procedures for dealing with "traditional" RTT bias do not circumvent the additional problem we have identified. We argue that if a reduced form estimation of RTT is undertaken, firm-year fixed effects must be added in order to eliminate this bias. Estimates from two large panel datasets from Portugal and Germany show that the bias is empirically important. Adding firm-year fixed effects to the regression increases estimates of RTT in the two respective countries by between 3.5% and 4.5% of wages at 20 years of tenure over 80% (50%) of the estimated RTT level itself. The results extend to tenure correlates used in macroeconomics such as the minimum unemployment rate since joining the firm. Adding firm-year fixed effects changes estimates of these effects also.

The determinants of mutual fund performance: A cross-country study

We use a new data set to study the determinants of the performance of open–end actively managed equity mutual funds in 27 countries. We find that mutual funds underperform the market overall. The results show important differences in the determinants of fund performance in the USA and elsewhere in the world. The US evidence of diminishing returns to scale is not a universal truth as the performance of funds located outside the USA and funds that invest overseas is not negatively affected by scale. Our findings suggest that the adverse scale effects in the USA are related to liquidity constraints faced by funds that, by virtue of their style, have to invest in small and domestic stocks. Country characteristics also explain fund performance. Funds located in countries with liquid stock markets and strong legal institutions display better performance.

CARTO-SOM - Cartogram creation using self-organizing maps

Dissertação apresentada como requisito parcial para obtenção do grau de Mestre em Ciência e Sistemas de Informação Geográfica

Database repairs with answer set programming

Dissertação para obtenção do Grau de Mestre em Engenharia Informática

Determinants of venture capital and private equity investments in renewable energy: A cross-country study

A Work Project, presented as part of the requirements for the Award of a Masters Degree in Economics from the NOVA – School of Business and Economics

Distributed replicated macro-components

Dissertação para obtenção do Grau de Mestre em Engenharia Informática

Urban containment: An effective tool for environmental protection?

This paper examines the effectiveness of urban containment policies to protect forestland from residential conversion and to increase the provision of forest public goods in the presence of irreversible investments and policy uncertainty. We develop a model of a single landowner that allows for switching between competing land uses (forestry and residential use) at some point in the future. Our results show that urban containment policies can protect (even if temporarily) forestland from being developed but must be supplemented with policies that influence the length and number of harvesting cycles if the goal is to increase nontimber benefits. The threat of a development prohibition creates incentives for preemptive timber harvesting and land conversion. In particular, threatened regulation creates an incentive to shorten rotation cycles to avoid costly land-use restrictions. However, it has an ambiguous effect on forestland conversion as the number of rotation cycles can also be adjusted to maximize the expected returns to land. Finally, in the presence of irreversibility, forestland conversion decisions should be done using real option theory rather than net present value analysis

Narrative Bifurcation, Cloud Computing Interfaces and Hitchcok

From a narratological perspective, this paper aims to address the theoretical issues concerning the functioning of the so called «narrative bifurcation» in data presentation and information retrieval. Its use in cyberspace calls for a reassessment as a storytelling device. Films have shown its fundamental role for the creation of suspense. Interactive fiction and games have unveiled the possibility of plots with multiple choices, giving continuity to cinema split-screen experiences. Using practical examples, this paper will show how this storytelling tool returns to its primitive form and ends up by conditioning cloud computing interface design.

Terminologia em uso na Direcção Nacional de Desenvolvimento Tecnológico e Inovação: a variação nos termos complexos

Inserido no âmbito do Projecto “Terminologia da Administração Pública – TERMAP”, o presente trabalho constitui uma análise descritiva de elementos discursivos que nos permitem dar conta da terminologia produzida na Direcção Nacional de Desenvolvimento Tecnológico e Inovação, do Ministério da Ciência e Tecnologia. Temos como objectivo a organização da terminologia da área, tendo em vista a fixação dos termos, permitindo assim uma melhor comunicação e transferência de conhecimento, quer a nível intra-institucional quer a nível interinstitucional, bem como a nível externo. Neste trabalho, partimos de uma abordagem semasiológica, e procuramos sempre ter em foco as especificidades discursivas, não pondo de parte, quando necessário, uma perspectiva mais onomasiológica. A abordagem proposta desenvolve-se em torno de cinco capítulos: a) o primeiro traz em revisão aspectos da organização e funcionamento da Administração Pública Central em Angola, na qual se insere o domínio de análise; b) o segundo consiste na análise dos aspectos relativos à constituição do corpus textual; c) os pressupostos teóricos apresentados no terceiro capítulo dizem respeito à formação dos termos complexos e aos fenómenos de variação em terminologia; d) no quarto capítulo, a análise volta ao corpus textual, mais propriamente ao seu tratamento. Neste capítulo apresentam-se os processos relativos à extracção e selecção dos candidatos a termos, e o levantamento dos casos de variação; e) o quinto capítulo é reservado à apresentação e análise dos dados. Fazemos uma proposta de um modelo de base de dados terminológica multilingue. Esta proposta surge na sequência da necessidade de fixar os termos, com vista à transferência de conhecimento.