Trade liberalization in Kenya started in the early 1980s with the structural adjustment programmes, and continued under the multilateral framework of the WTO. During the same period, the incidence of poverty and level of inequality also worsened. The government’s focus on trade negotiations has been to ensure that there is policy space for the daily running of the economy even though welfare impacts are also important. Non-state actors have argued that trade liberalization has negatively affected the poor; particularly the farmers, since they cannot compete with the developed countries whose farmers enjoy significant government support through subsidies, making their products much cheaper in the world market. Government officials, on the other hand, contend that trade liberalization is good as it brings in competition and transfer of technology which is good for an economy. It is important to examine how trade liberalization has affected household’s welfare in Kenya, given that this kind of analysis has not been conducted in Kenya. This study is unique because it does not assume the existence of a trade liberalization– poverty relationship, unlike most studies. It uses a multi-method approach to first test the hypothesis that there is no statistically significant relationship between trade liberalization and poverty, it further tests for multiplier effects of trade liberalization on poverty determinants. Trade Liberalization and poverty is found to have a stochastic relationship, furthermore investments and capital stock were found to significantly affect poverty determinants in the stochastic model. Due to unavailability of household welfare measure data in time series, a CGE model was used to establish the dynamics of trade liberalization on poverty at a point in time using the 2003 Social Accounting Matrix Data for Kenya. Overall, trade liberalization accompanied by FDI had the greatest impact on household welfare. Trade liberalization had a positive impact on household welfare since household incomes and consumption increased. Micro simulations results, based on changes in consumption, also showed that poverty incidence reduced for all households, even though the urban households experienced higher decreases. The study found that there was little difference in protecting sensitive products and not protecting them; secondly, trade liberalization accompanied by foreign direct investment had greater impact on improving the household welfare. Consumption and incomes increased, resulting in overall poverty reduction. The welfare of urban households was much higher than rural households in terms of income and consumption increases. However, income inequality was much higher in urban than rural areas. / Economics / D. Litt. et Phil. (Economics)

L’objet de cette thèse est d’analyser comment la politique de la concurrence peut être utilisée pour améliorer le pouvoir d’achat en générant des baisses de prix et affecter la répartition des revenus. L’évaluation des conséquences sur le bien-être de l’entrée de nouveaux concurrents sur un marché a fait l’objet d’une littérature importante. Mais elle repose sur des analyses en équilibre partiel et une approche complémentaire en terme d’équilibre général peut être utile. D’autres analyses de la politique de la concurrence en terme d’équilibre général ont été effectuées pour des économies avec des rendements d’échelle croissants.Cependant, dans la mesure où il semble discutable que les secteurs dans lesquels les rendements d’échelle sont croissants soient majoritaires dans les économies réelles, il apparaît pertinent d’analyser les effets de l’entrée dans des économies "convexes". Nous nous appuyons ainsi sur des modèles simples d’équilibre général pour étudier les conséquences de la politique de la concurrence - en matière d’entrée, de fusions etc... - sur le bien-être. Afin d’analyser ses effets distributifs, nous considérons des économies composées d’agents qui se distinguent par la nature des facteurs qu’ils offrent. Nous supposons en particulier que l’un d’eux fournit une quantité de travail exogène, que nous endogénéisons par la suite. Nous montrons ainsi que la politique de la concurrence peut être conflictuelle : elle peut ne pas impacter tous les consommateurs de la même façon et bénéficier à certains, au détriment d’autres. / This thesis consists in analysing how competition policy by enhancing prices decreases,may be used to boost purchasing power and influence income distribution. A huge literature deals with the evaluation of how entry of firms within a particular sector improves welfare. But this literature mainly relies on a partial equilibrium approach. To complete this approach, a general equilibrium view point on competition policy is called for. There have been several attempts to study the welfare effects of entry in general equilibrium economies with increasing returns to scale. However, it is not clear that pervasive unexploited increasing returns to scale exist in real economies. Therefore, it seems relevant to consider the case of "convex" economies. In this perspective, we use simple general equilibrium models to examine how competition policy - with regard to entry or mergers - affects welfare. In order to study the redistributive effects of competition policy, we consider the case where several agents supply different inputs (the supply of labor is first considered as exogenous,and then endogenous). We show that competition policy is not always welfare improving for all agents.

L’objectif de cette thèse consiste à élaborer un modèle d’équilibre général calculable adapté à l’analyse de la politique de soutien au biodiesel en France. Le gouvernement français a décidé récemment de supprimer l’exonération partielle de TICPE qui était jusqu’à présent la principale aide aux biocarburants de première génération. Cette mesure pourrait compromettre l’avenir de ce secteur en l’absence d’un nouveau système d’incitations. Notre modèle vise d’une part à mesurer les conséquences de ce changement réglementaire sur les différentes activités économiques; et d’autre part à évaluer les impacts d’un dispositif alternatif de soutien au biodiesel fondé sur un relèvement de la fiscalité sur le gazole. L’étude tient compte de la contribution des fluctuations du prix du pétrole à cet objectif. La matrice de comptabilité sociale servant de base empirique au modèle est fondée sur l’année de référence 2009. Elle comprend 3 facteurs de production, et 17 biens et secteurs d’activité. La désagrégation des secteurs agricoles et agroalimentaires fait apparaître la chaîne de production du biodiesel de manière détaillée. Le modèle intègre également des spécifications permettant de représenter le rôle des coproduits du biodiesel et les changements d’affectation des sols. Les résultats des simulations suggèrent que l’objectif d’incorporation de 10% à l’horizon 2020 requis par la directive européenne de 2009 pourrait être atteint par un relèvement de la TICPE sur le gazole à un niveau comparable à celui en vigueur sur le carburant essence. Cependant, les effets récessifs observés sur un certain nombre de variables conduisent à tempérer l’opportunité d’adopter une telle mesure. / The objective of this thesis is to build a computable general equilibrium model for the analysis of the public support policy to biodiesel in France. The French government has recently decided to remove the partial exemption from the excise tax on fuels that was until now the main support instrument to promote first-generation biofuels. This modification could affect the profitability of the biofuels’ and connected activities. In this context, our model aims on the one hand to quantifies the consequences of this policy change throughout the national economy; on the other hand, it assesses the impacts of an alternative support scheme based on higher taxes on conventional diesel. The study also takes into account the influence of oil price fluctuations in the analysis. The social accounting matrix (SAM) used as empirical basis is built on the 2009 reference year. It includes three production factors, and seventeen goods and activity sectors. The disaggregation of agricultural and agribusiness sectors emphasizes the whole biodiesel production chain. Energy substitution is reflected through multi-stages nested production and consumption structures. In line with recent studies, the model also specifies the role of biodiesel by-products in the livestock sector, and analyses the land use changes. Different scenarios are implemented to isolate the effects of changes in the support system. Results of simulations suggest that the 10% penetration rate targeted by the 2009 European directive by 2020 could be reached with taxes on diesel as high as on gasoline. However, recessive impacts observed in many sectors mitigate the opportunity to adopt such an alternative support policy.

Dans un contexte de croissance effrénée de la demande mondiale d'énergie et de pression environnementale pour lutter contre le réchauffement climatique, cette thèse étudie une des technologies envisagées pour réduire les émissions de dioxyde de carbone (CO2) : la capture et le stockage géologique du carbone (CSC). Nous étudions principalement l’application de cette technologie à la production des bioénergies (BCSC) car ce procédé permet d’épurer l’atmosphère tout en fournissant un substitut énergétique non polluant aux énergies fossiles. La première partie de ce travail analyse le potentiel économique et environnemental de la technologie de BCSC. Tout d'abord, une évaluation économique et environnementale de la BCSC dans le secteur de la production de bioéthanol en France est conduite.Ensuite, grâce à un modèle bottom-up d’optimisation TIAM-FR, nous étudions le potentiel global et régional de cette technologie dans le secteur de l'électricité. Enfin, les incitations économiques à mettre en place pour assurer son développement sont mises en évidences. Dans la deuxième partie, un modèle d'équilibre général calculable est utilisé pour évaluer les politiques environnementales. Nous construisons le modèle théorique en introduisant les technologies de CSC et de BCSC ainsi qu’une large variété d’instruments économiques. Le modèle est ensuite calibré pour comparer l’efficacité économique des instruments de politique environnementale à un niveau mondial et à un niveau français. / In a context of unbridled growth of global energy demand and environmental pressure in the fight againstglobal warming, this thesis studies one of the proposed technologies to reduce carbon dioxide (CO2)emissions: carbon capture and geological storage (CCS). We therefore consider the application of thistechnology to the production of bioenergies (BCCS) because this technology allows purifying theatmosphere while providing a clean energy alternative to fossil fuels. The first part of this work analyzesthe economic and environmental potential of BCCS. First, an economic and environmental assessment ofBCCS in the bioethanol production in France is conducted. Then, using the bottom-up optimization modelTIAM-FR, we study the global and regional potential of this technology in the electricity sector. Finally,the economic incentives that need to be provided to ensure BCCS deployment are highlighted. In thesecond part, a general equilibrium model is used to evaluate environmental policies. We construct thetheoretical model by introducing the CCS and BCCS as well as a wide range of economic instruments.The model is then calibrated to compare the effectiveness of environmental policy instruments at a globallevel and at a French level.

O objetivo deste trabalho é investigar o desempenho de estimadores baseados em momentos das famílias verossimilhança empírica generalizada (GEL) e mínimo contraste generalizado (GMC) na estimação de modelos de equilíbrio geral dinâmico e estocástico (DSGE), com enfoque na análise de robustez sob má-especificação, recorrente neste tipo de modelo. Como benchmark utilizamos método do momentos generalizado (GMM), máxima verossimilhança (ML) e inferência bayesiana (BI). Trabalhamos com um modelo de ciclos reais de negócios (RBC) que pode ser considerado o núcleo de modelos DSGE, apresenta dificuldades similares e facilita a análise dos resultados devido ao menor número de parâmetros. Verificamos por meio de experimentos de Monte Carlo se os estimadores estudados entregam resultados satisfatórios em termos de média, mediana, viés, erro quadrático médio, erro absoluto médio e verificamos a distribuição das estimativas geradas por cada estimador. Dentre os principais resultados estão: (i) o estimador verossimilhança empírica (EL) - assim como sua versão com condições de momento suavizadas (SEL) - e a inferência bayesiana (BI) foram, nesta ordem, os que obtiveram os melhores desempenhos, inclusive nos casos de especificação incorreta; (ii) os estimadores continous updating empirical likelihood (CUE), mínima distância de Hellinger (HD), exponential tilting (ET) e suas versões suavizadas apresentaram desempenho comparativo intermediário; (iii) o desempenho dos estimadores exponentially tilted empirical likelihood (ETEL), exponential tilting Hellinger distance (ETHD) e suas versões suavizadas foi bastante comprometido pela ocorrência de estimativas atípicas; (iv) as versões com e sem suavização das condições de momento dos estimadores das famílias GEL/GMC apresentaram desempenhos muito similares; (v) os estimadores GMM, principalmente no caso sobreidentificado, e ML apresentaram desempenhos consideravelmente abaixo de boa parte de seus concorrentes / The objective of this work is to investigate the performance of moment-based estimators of the generalized empirical likelihood (GEL) and generalized minimum contrast (GMC) families in the estimation of dynamic stochastic general equilibrium (DSGE) models, focusing on the robustness analysis under misspecification, recurrent in this model. As benchmark we used generalized method of moments (GMM), maximum likelihood (ML) and Bayesian inference (BI). We work with a real business cycle (RBC) model that can be considered the core of DSGE models, presents similar difficulties and facilitates the analysis of results due to lower number of parameters. We verified, via Monte Carlo experiments, whether the studied estimators presented satisfactory results in terms of mean, median, bias, mean square error, mean absolute error and we verified the distribution of the estimates generated by each estimator. Among the main results are: (i) empirical likelihood (EL) estimator - as well as its version with smoothed moment conditions (SEL) - and Bayesian inference (BI) were, in that order, the ones that obtained the best performances, even in misspecification cases; (ii) continuous updating empirical likelihood (CUE), minimum Hellinger distance (HD), exponential tilting (ET) estimators and their smoothed versions exhibit intermediate comparative performance; (iii) performance of exponentially tilted empirical likelihood (ETEL), exponential tilting Hellinger distance (ETHD) and its smoothed versions was seriously compromised by atypical estimates; (iv) smoothed and non-smoothed GEL/GMC estimators exhibit very similar performances; (v) GMM, especially in the over-identified case, and ML estimators had lower performance than their competitors

Près de deux décennies, après la libéralisation de l’économie tunisienne, les disparités régionales se sont fortement accentuées. Les amples écarts de développement entre les régions du littoral et de l’intérieur sont révélateurs d’une grande hétérogénéité en termes de niveaux de revenus, de croissance, de chômage, de répartition entre activités à forte et à faible productivités et de pauvreté. Si les régions du littoral font partie de l’axe de compétitivité et constituent le centre des branches phares de l’industrie tunisienne, les autres régions de l’intérieur disposent de moins de compétences stratégiques et affichent des performances moyennes, voire même faibles. Aucun processus de convergence régionale n’est enclenché. L’objet de la thèse est de quantifier et d’appréhender les impacts macroéconomiques et microéconomiques de sept réformes de politiques économiques susceptibles de réduire les disparités régionales, dans le cadre d’une approche macro-micro. Approche qui conduit inévitablement à privilégier un cadre d’analyse qui se compose de deux modèles reliés: un modèle d’équilibre général dynamique et multirégional et un modèle de micro simulation. L’implémentation de ces deux modèles a permis de réaliser un exercice de projection et un autre de simulation. Le premier exercice a étudié l’évolution future de l’économie tunisienne, en absence de toutes réformes économiques et/ou choc exogène. Les résultats montrent que le clivage littoral-intérieur devrait s’accentuer si des mesures de correction ne sont pas mises en œuvre. Les résultats de simulation suggèrent qu’une politique de libéralisation commerciale bénéficie plus aux régions du littoral. Pour stimuler la croissance des régions de l’intérieur, il est préférable d’entreprendre des politiques de discrimination positive qui visent à augmenter leurs niveaux d’investissements public et surtout privé. Par ailleurs, la réduction de l’écart de performance économique entre le littoral et l’intérieur du pays ne peut se faire rapidement qu’au moyen d’un changement technologique important dans les régions de l’intérieur. Tous les scénarios envisagés dans ce travail rejettent la nécessité d’un arbitrage entre croissance et pauvreté régionales et confirment donc les possibilités d’une croissance pro-pauvre. / Almost two decades after the liberalization of the Tunisian economy, regional disparities have been accentuated severely and are expected to grow further. The existing gap between the coastal regions and those inland is showing high inequality in terms of levels of income, growth, unemployment, productivity and poverty. The industry in the littoral regions remains the most competitive leading the Tunisian industry, while other regions in the interior lag behind with fewer strategic competences and skills and medium or even low performance. Hence, the process of regional convergence has been broken rather than achieved. The purpose of this research is to assess and quantify the macroeconomic and microeconomic impacts of seven economic policies which aiming to reduce regional disparities in Tunisia. For that purpose, we will use a micro-macro based approach with two interconnected models: A multiregional dynamic general-equilibrium model and a micro-simulation model. The implementation of these two models has enabled a projection exercise and simulation one. The first exercise studied the future evolution of the Tunisian economy in its national and regional dimensions without any economic and / or exogenous shock reforms. The results show that the littoral-internal cleavage is expected to increase if corrective measures will not be implemented. Simulation results show that trade liberalization policy benefits more to coastal regions. However, to stimulate growth performance on behalf of inland regions, positive discrimination action policies, as public and especially private investment increase, will be necessary. Moreover, reducing the economic gap performance between the coast and the interior can be done quickly through a major technological change for regions in the interior. All scenarios in this study reject the possibility of trade-off between growth and regional poverty and thus confirm the potential for pro-poor growth.

以往財務理論在討論財務市場行為時，均是在完全市場( e market)的假 設上做分析。但是從現實的角度來看，由於時間 (time)與不確定(uncertainty) 等因素，導致市場往往是不完全的(incomplete)；亦即資產或證券的數目往往小 於未來各種可能發生的不確定狀態的數目。當各種不同狀態事件發生時,如果沒有足夠的 資產或證券工具來涵括(span)所有投資人所欲達成的跨時所得移轉，則有某些風 險因子不能以既有的財務工具來複製，此時投資人將無法完全地規避該項風險。 本文的分析方法屬於微分拓樸數學工具的應用。從基本可微分流行(differentiable manifold) 性質，我們可得到整體性的觀點，優於以往在歐氏空間，Hilbert 空 間等拓樸空間只考慮在局部的性質.首先由最基本平滑流形(smooth manifo-[念 切入，介紹平滑流形與歐氏空間的關係。再由市場均衡的定義找出均衡流形( equilibrium manifold)。結合Debreu(1970)與Balasko(1976,1988) 建立的正 規經濟，探討其性質.加入財務市場時，透過正規經濟的理論，證明不完全財物 市場均衡generic 存在性。最後，利用不完全財務市場均衡generic的存在性，證明單 一商品及多商品的資本資產定價(CAPM)；並且建立一以消費為基礎的資本資 產定價模式。

This thesis consists of four essays within the field of environmental economics. Computable General Equilibrium models have been used to assess the economic consequences of greenhouse gas policies. The focus is mainly on the Swedish economy, but the EU economies and the global economies are also analyzed in one essay each. The costs and effects of a unilateral Swedish decision to reduce carbon dioxide emissions are analyzed in essay I. The results of a unilateral reduction are compared to the results of an implementation of an EU multilateral agreement. The results indicate that if Sweden unilaterally decides to increase its CO2 tax, total EU CO2 emissions will increase, i.e. there will be a “carbon leakage effect”. Furthermore, an EU multilateral implementation of a CO2 tax will induce lower welfare (excluding environmental benefits) in Sweden, as compared to the situation where the same tax is unilaterally introduced.In the second essay we analyze the Swedish environmental goals conforming to the Kyoto Protocol, when simultaneously meeting national goals to alleviate acidification and eutrofication effects by reducing SO2 and NOx pollutants. We have found that when secondary benefits of measures aiming at reducing CO2 are taken into account, it may still be in the government’s interest to nationally decrease CO2, instead of engaging in seemingly low-cost trading. The principles for allocation emission permits are many, and in the third essay I focus on principles based on economic welfare theory. My main conclusion from these simulation exercises is that the distribution rule based on the different assumptions on social welfare function and some other more ad hoc distribution rules offers quite large changes in welfare, distributions of emission rights and contrary to earlier literature, I find that the initial distribution not only gives second-order effects but affects equilibrium prices and therefore, income.In the fourth essay I focus on how households’ demand for transport services can be improved in CGE-models. A differentiation between trip purposes and trip length, a complementary relationship between work journeys and labor supply, and a subdivision of households by density of population and income, influences the numerical results in a direction increasing the negative welfare effect of a carbon target, as compared to the non-extended model. / Diss. Stockholm : Handelshögskolan, 2004

La scelta del modeller riguardo alla chiusura del modello CGE influenza i suoi risultati finali e le sue prescrizioni di policy. In questa tesi, lo scopo è l’analisi e l’identificazione del problema, sia attraverso una discussione teorica che un’ applicazione pratica. Dall’articolo del 1963 di Amartya Sen in poi, la letteratura ha presentato vari articoli sull’argomento. Attualmente, il problema delle chiusure del modello non appare più centrale nel dibattito. Dopo una breve introduzione su cosa siano i CGE, il loro sviluppo e la loro struttura, è presentata una serie di esemplificative maquette con lo scopo di introdurre al concetto di chiusura, come essa influenzi i risultati e come questa scelta del modeller sia intimamente connessa ai fondamenti macroeconomici del sistema. Dopo la teoria, ci si sposta nel mondo reale analizzando con differenti modelli (Neoclassico, “Bastardo Keynesiano”, Strutturalista/Post- Keynesiano) e diverse chiusure per gli aggregati macroeconomici (risparmi privati, pubblici, e stranieri) l’impatto dell’accordo regionale SADC sull’economia mozambicana. I modelli CGE per il Mozambico sono calibrati su una SAM del 2003 e sono svolti con l’ausilio di GAMS/MPSGE. I risultati dimostrano che la chiusura influenza i risultati stessi del modello per cui ognuno presenta una serie di raccomandazioni politiche per l’applicazione dell’accordo SADC. / Modellers’ choice on closure rules affects a CGE model results and consequently its policy prescriptions. In this thesis, the aim is to detect and assess this issue, both through a theoretical discussion and an empirical application. Starting from Amartya Sen’s 1963 paper, literature presents many contributions on this topic. Currently, the closure rule problem is not central in the CGE debate. After a brief introduction on CGEs, their development and their structure, a series of simple maquette is presented. They have the exemplary role of introducing the concept of closures, explain how they affect final outcomes and how this modeller’s choice is strictly connected to the macroeconomic foundation of the economic system. After theory, we move into the real World analyzing through different models (Neoclassical, “Bastard Keynesian”, and Structuralist/ Post- Keynesian), and through different closure rules for macro- aggregates (private, public and foreign savings) the impact of the Regional Trade Agreement of SADC with respect to the Mozambican economy. The Mozambican CGE models are calibrated on a 2003 Social Accounting Matrix (SAM) and they are performed using GAMS/ MPSGE. Outcomes show that closure rules affect them and each model presents a set of policy prescription to implement the SADC agreement.

With the internationalization of financial markets, short-term capital flows to emerging market economies have become an important phenomenon in the world. The papers in this dissertation are concerned with investigating the effects of such flows in the receiving countries. The analysis is cast in a dynamic general equilibrium framework for small open economies. Two of the papers are quantitative investigations of the forces at work in small and relatively poor economies that liberalize trade and capital flows. The common approach of these papers is that of a computational experiment: calibrated simulations constitute a test of whether the models can explain certain dynamics which we observe in the data. The first paper investigates whether a calibrated two-sector neoclassical growth model can explain the magnitudes and the timing of capital flows in the Baltic countries after the fall of the Soviet Union. The results indicate that it can, and that the large and persistent trade deficits which we observe in the data need not be a reason to worry. However, the model also tells us that a reversal of capital flows and large sectoral adjustments lie ahead of the Baltic countries. In the second paper, the focus is on modelling the observed co-movement between consumption and the real exchange rate in Spain, which experienced large capital inflows following the entry into the European Community in 1986. In accordance with episodes of trade liberalization elsewhere, consumption in Spain boomed and the real exchange rate appreciated for several years after 1986. Standard two-sector models with traded and non-traded goods have problems accounting for these facts. The paper explores some mechanisms that can improve the standard modelling framework, and evaluates their quantitative importance in calibrated simulations for Spain. The third paper studies the government’s optimal bailout policy in an environment where sudden stops of capital flows cause financial crises in a small open economy. Real world events, such as the financial crises in the South East Asian countries in 1997, motivate the analysis. Compared to the previous essays, the paper is different in its nature in that it develops a highly stylized environment to analytically study the government’s optimal bailout policy. The paper shows that the government should optimally commit to a policy that only partially protects private debtors against inefficient liquidation. / Diss. Stockholm : Handelshögsk., 2004