We analyse the dynamics of the standard deviation of demand and supply shocks as well as of the demand component of GDP across countries in the European Monetary Union (EMU). This analysis allows us to evaluate the patterns of cyclical comovement in EMU and compare them the cyclical performance of the new members of the EU and other OECD countries. We make use of sigma-convergence methods to identify synchronization patterns in business cycles. The Eurozone has converged to a stable lower level of dispersion across business cycles during the end of the 80s and the beginning of the 90s. The new EU members have also experienced a strong pattern of convergence from 1998 to 2005, when a strong divergence trend appears. An enlargement of the EMU to 22 members would not significantly decrease its optimality as a currency area. There is evidence for some Europe-specific characteristics as compared to global comovements in business cycles. (authors' abstract)

[pt] A partir do método de Rigobon (2001) para identificação de um sistema de equações simultâneas na presença de heterocedasticidade, aprofundamos a discussão sobre a relação entre os preços internacionais de commodities e o câmbio real para países com determinadas características. Ao contrário da abordagem tradicional da literatura de commodity currency nesta dissertação admitimos a possibilidade dos preços de commodities serem endógenos em relação à taxa de câmbio, trabalhamos com séries que incorporam mais de um regime cambial e, através de diversas simulações, encontramos evidências de que hipóteses sobre a estacionariedade das séries, em torno da raiz unitária, não afetam significativamente os resultados do exercício empírico. Salvo algumas restrições, os resultados derivados sugerem que o câmbio real do Brasil deve apreciar em resposta a elevações nos preços internacionais das principais commodities que exporta, mas a elasticidade dos preços de commodities em relação ao câmbio não pode ser considerada estatisticamente diferente de zero. Para a Nova Zelândia, as evidências indicam que os efeitos contemporâneos dos movimentos da taxa de câmbio sobre os preços das suas principais commodities exportadas é significativo, embora o efeito dos preços das commodities sobre o câmbio deva ser considerado estatisticamente igual a zero. / [en] Using Rigobons (2001) identification method for simultaneous equations models, based on the heteroskedasticity of the structural shocks, we analyze the relationship between the exchange rate and commodity prices for specific countries. Instead of the traditional approach of the commodity currency literature, we allow for endogenous effects of the exchange rates on the commodity prices, and we work with series that span two exchange rate regimes. From the results of some simulations, we also find out that the lack of assumptions about the stationarity of the series, close to the unity root, do not harm the conclusions of the empirical exercise. In spite of some caveats, the results of the empirical investigation suggest that the real exchange rate of Brazil should appreciate in response to a rise in the prices of its most important export commodities. However, the elasticity of the commodity prices to the exchange rate can not be considered different from zero, implicating that the country does not have much market power in the trade of these commodities. For New Zealand, the evidence indicates that exchange rate variations are important for the determination of the commodity prices, although the impact of commodity prices on the exchange rate is statistically equal to zero.

Bien que les pays de l’Europe Centrale et Orientale montrent de plus en plus des similitudes structurelles avec des pays développés, leurs économies restent vulnérables aux facteurs d’instabilité financière caractéristiques aux pays en développement. La présence de ces vulnérabilités a conduit aux débats sur les avantages de l’adhésion rapide à l’Union Economique et Monétaire (UEM). Traditionnellement, selon de la Théorie des Zones Monétaires Optimales, l’adoption de l’euro peut être bénéfique éliminant le risque du taux de change, donnant un meilleur accès au financement externe et atténuant l’impact des crises financières. De l’autre côté, l’abandon de l’autonomie de la politique monétaire et du taux de change prive les autorités nationales d’une marge de manœuvre dans le cas où le pays soit touché par les chocs asymétriques (d’offre) ou sa réponse aux chocs symétriques diverge de celle de la zone monétaire. L’objective de cette thèse est de déterminer les vulnérabilités financières des PECO et le degré d’asymétrie de leurs économies afin de participer aux débats sur la stratégie d’adhésion à l’euro. / Although the Central and Eastern European countries show in many respects increasing similarities to developed economies they still present some characteristics pointing to potential sources of increased financial vulnerability. The presence of these vulnerabilities has raised the discussion about whether early euro adoption could represent an effective policy remedy for the CEECs’ economies. Traditionally, in the sense of the Optimum Currency Area (OCA) Theory, the arguments vary between two points of view. On the one side, the EMU adhesion would have a beneficial effect eliminating exchange rate risks, giving a better access to external financing and attenuating the impact of financial crises. On the other side, EMU membership may not protect these countries against asymmetric shocks. In fact, in the case of (real) asymmetric shocks or asymmetric response to common (real and nominal) shocks, the output and employment costs of the euro adoption could be very high. The objective of this dissertation is to study these issues, focusing first on potential source of financial vulnerabilities, and then to assess the degree of the CEECs’ shock asymmetry to participate in debates on the euro adoption.