A relational algebra approach to ETL modeling

The MAP-i Doctoral Programme in Informatics, of the Universities of Minho, Aveiro and Porto

A dispensa de prestação de garantia em processo de execução fiscal e a prova de factos negativos da inexistência ou insuficiência de bens do executado

Dissertação de mestrado em Direito Tributário e Fiscal

A sucessão em sede de reversão do processo de execução fiscal

Dissertação de mestrado em Direito Tributário e Fiscal

Sinistralidade rodoviária e o marketing relacional: perspetivas de soluções mais eficazes no seu combate em Portugal

Dissertação de mestrado em Marketing e Estratégia

Gestão sustentável de águas pluviais em ambiente urbano

Dissertação de mestrado integrado em Engenharia Civil

Compatibilidade do contrato de concessão comercial com as regras de defesa da concorrência

Dissertação de mestrado em Direito dos Contratos e da Empresa

Odour nuisance in Ireland and the potential use of olfactometry for the control of odours

Odour nuisance in other European countries has led to the development of techniques which employ panels of human assessors for the determination of environmental odours. Odour measurement is not widely practised in Ireland, yet local authorities are frequently in receipt of odour derived public complaints. This dissertation examines the fundamentals of odour nuisance in terms of how we perceive odours, common sources of environmental odours, the principles of odour measurement (in particular the Sutch pre-standard on olfactometry) and the extent to which odour nuisance is a problem in Ireland. The intention is to provide a reference document for use by those interested parties in the country who may be variously involved in policy making, legislative development, enforcement of environmental law or any person who has an interest in odours and the public nuisance they can give rise to. In particular the aim was to provide previously undocumented information on the prevalence of odour nuisance in Ireland, the exercision of the available powers to control odours, and the possible value of odour measurement as part of a regulatory process. A questionnaire was circulated to all local authorities in the country and 82% responded with information on their experiences and views on the subject of odours. The results of the survey are presented in summary and detailed form.

Does illegal immigration empower rightist parties?

The main goal of this paper is to analyze the political outcome in countries where the relevant issue in elections is the control of immigration. In particular we explore the consequences on the political outcome of the fact that parties are either ideological or opportunistic with respect to this issue. In order to do that we use a simple two-party political competition model in which the issues over which parties take positions are the level of border enforcement and the way it has to be ?nanced. We show that an ideological rather than a pure opportunistic behavior gives parties an advantage to win the election. In particular, in most of the cases we consider we ?nd that rightist parties have an advantage to win in countries where the relevant issue in election is illegal immigration. This result may help us to understand the recent success of anti-immigrant and rightist parties in several countries.

Environmental regulation: choice of instruments under imperfect compliance

Compliance is an important issue in environmental regulation. In this paper, we discuss some of the key elements of the problem and analyze a situation where emissions are not random and firms are risk-neutral. We study the firm's decision on emissions and compliance when the environmental regulation is based on standards and the enforcement agency audits the firm with a certain probability. We then compare total emissions when environmental regulation is based on different instruments: standards, taxes, and tradable permits. We show that when compliance is an issue, environmental taxes are superior to the other instruments. We also analyze the (static) efficiency of the solution.

A General model of bilateral migration agreements

Unilateral migration policies impose externalities on other countries. In order to try to internalize these externalities, countries sign bilateral migration agreements. One element of these agreements is the emphasis on enforcing migration policies: immigrant-receiving countries agree to allow more immigrants from their emigrant-sending partner if they cooperate in enforcing their migration policy at the border. I present a simple theoretical model that justifies this behavior in a two-country setting with welfare maximizing governments. These governments establish migration quotas that need to be enforced at a cost. I prove that uncoordinated migration policies are inefficient. Both countries can improve welfare by exchanging a more "generous" migration quota for expenditure on enforcement policy. Contrary to what could be expected, this result does not depend on the enforcement technology that both countries employ.

Lowering blood alcohol content levels to save lives: The european experience

Road safety has become an increasing concern in developed countries due to the significant amount of mortal victims and the economic losses derived. Only in 2005 these losses rose to 200.000 million euros, a significant amount - approximately the 2% of its GDP- that easily justifies any public intervention. One tool used by governments to face this challenge is the enactment of stricter policies and regulations. Since drunk driving is one of the most important concerns of public authorities on this field, several European countries decided to lower their illegal Blood Alcohol Content levels to 0.5 mg/ml during the last decade. This study evaluates for the first time the effectiveness of this transition using European panel-based data (CARE) for the period 1991-2003 using the Differences-in-Differences method in a fixed effects estimation that allows for any pattern of correlation (Cluster-Robust). My results show the existence of positive impacts on certain groups of road users and for the whole population when the policy is accompanied by some enforcement interventions. Moreover, a time lag of more than two years is found in that effectiveness. Finally, I also assert the importance of controlling for serial correlation in the evaluation of this kind of policies.

International Corporate Taxation and U.S. Multinationals’ Behavior: an Integrated Approach

Using data from the International Revenue Service, this paper explores the effcts of corporate taxation on U.S. capital invested abroad and on tax planning practices (dividend payments, income shifting, and passive investment). The econometric analysis first indicates that investment is strongly influenced by average tax rates, with a magnified impact for particularly low-tax rates implying that the attractiveness of low-tax countries is not weakened by anti-deferral rules and cross-crediting limitations. Further explorations suggest that firms report higher profit and are less likely to repatriate dividends when they are located in low-tax jurisdictions. Firms also report higher Subpart F income in countries in which they shift their profit, suggesting that cross-crediting provides an incentive to shift passive income in low-tax countries and that passive investment can be an alternative strategy to minimize taxes when active investment opportunities are lacking. Finally, the paper estimates the role of effective transfer pricing regulation on income shifting activities using the quality of host countries' law enforcement. It appears that low degrees of law enforcement are associated with higher income-shifting.

Decision Errors, Legal Uncertainty and Welfare: a General Treatment

This paper provides a general treatment of the implications for welfare of legal uncertainty. We distinguish legal uncertainty from decision errors: though the former can be influenced by the latter, the latter are neither necessary nor sufficient for the existence of legal uncertainty. We show that an increase in decision errors will always reduce welfare. However, for any given level of decision errors, information structures involving more legal uncertainty can improve welfare. This holds always, even when there is complete legal uncertainty, when sanctions on socially harmful actions are set at their optimal level. This transforms radically one’s perception about the “costs” of legal uncertainty. We also provide general proofs for two results, previously established under restrictive assumptions. The first is that Effects-Based enforcement procedures may welfare dominate Per Se (or object-based) procedures and will always do so when sanctions are optimally set. The second is that optimal sanctions may well be higher under enforcement procedures involving more legal uncertainty.

Disputes, Debt and Equity

We show how the prospect of disputes over firms’ revenue reports promotes debt financing over equity. These findings are presented within a costly state verification model with a risk averse entrepreneur. The prospect of disputes encourages incentive regimes which limit penalties and avoid stochastic monitoring, even when the lender can commit to stochastic enforcement strategies. Consequently, optimal contracts shift away from equity and toward standard debt. For a useful special case of the model, closed form solutions are presented for leverage and consumption allocations under efficient debt contracts.

Dynamic Relational Contracts under Complete Information

This paper considers a long-term relationship between two agents who both undertake a costly action or investment that together produces a joint benefit. Agents have an opportunity to expropriate some of the joint benefit for their own use. Two cases are considered: (i) where agents are risk neutral and are subject to limited liability constraints and (ii) where agents are risk averse, have quasi-linear preferences in consumption and actions but where limited liability constraints do not bind. The question asked is how to structure the investments and division of the surplus over time so as to avoid expropriation. In the risk-neutral case, there may be an initial phase in which one agent overinvests and the other underinvests. However, both actions and surplus converge monotonically to a stationary state in which there is no overinvestment and surplus is at its maximum subject to the constraints. In the risk-averse case, there is no overinvestment. For this case, we establish that dynamics may or may not be monotonic depending on whether or not it is possible to sustain a first-best allocation. If the first-best allocation is not sustainable, then there is a trade-off between risk sharing and surplus maximization. In general, surplus will not be at its constrained maximum even in the long run.