Face à l’instabilité des cours agricoles et à ses conséquences notamment pour les pays en développement, la première partie de cette thèse est consacrée à la présentation des déterminants des cours des matières premières alimentaires, incluant les évolutions récentes en matière d’offre, en tenant compte des conséquences du réchauffement climatique, et de demande, considérant notamment les biocarburants. Il est également question de présenter la financiarisation en cours des économies, et les doutes qui planent sur le rôle que peuvent avoir la spéculation sur les marchés à terme ou encore la mise en œuvre des politiques monétaires, sur les cours au comptant observés sur les marchés physiques des produits agricoles. Suite aux réflexions et éléments de littérature avancés, la seconde partie procède de deux études empiriques. La première est axée sur l’impact de la spéculation sur les marchés financiers à terme sur le cours des sous-jacents (agricoles), alors que la seconde questionne le rôle des marchés monétaires, abordé à travers la capacité du banquier central à stabiliser les taux d’intérêt à court terme. Sur cette base, des conclusions mais également des pistes de recherche sont établies, du fait du prolongement en cours du processus de financiarisation des économies. / Faced with instability of agricultural commodities’ prices and its consequences especially for developing countries, the first part of this thesis is devoted to the presentation of food commodities’ prices, including recent developments with respect to the offering, taking into account the consequences of global warming and demand, as well as the importance of biofuels. It is also question to present the financialization of economies, and the doubts that take over the role of speculation on the futures markets or the implementation of monetary policies, on the spot prices observed on physical agricultural commodities markets. Following the advanced literature reflections and elements, the second part proceeds of two empirical studies, the first one focused on the impact of speculation about the financial futures markets on the underlying asset’s price (agricultural), while the second one examines the role of money markets through the capacities of the central banker to stabilize short-term interest rates. On this basis, conclusions but also future research are established due to the continuation of the economies financialization process.

The aim of this study is to explore ways to maximise the economic returns of road infrastructure investment. In order to achieve this objective, the study was divided into five parts involving the following: analysing the nature of road infrastructure, determining the relationship between road infrastructure investment and economic development, considering aspects of economic modelling, developing a formula of road investment, and refocusing road investment practices. In the first part the characteristics of road infrastructure are examined and the demand and supply approaches to road investment outlined. The focus is on the balanced approach versus the unbalanced approach to infrastructure investment. The second part analyses the causal relationship between road investment and economic development. Four components are highlighted, namely the investment component, the network-performance component, the transport economic component and the economic development component. The third part analyses the applicability of modelling techniques. In the fifth part, the formula of road investment and economic development is focused on four markets. Finally, it is argued that road infrastructure investment must be refocused. The following was found: Road infrastructure investment must be demand led. This is because of the characteristics of roads, namely their indivisibility, long gestation period, lumpiness and high cost. Road infrastructure investment can only realise economic development if the four causality components are complied with simultaneously. Input-output modelling is preferred in South Africa. The modelling strategy developed in this study is recommended for transport economic studies. The probability of economic returns of road infrastructure investment is a function of the real estate market, the land development market, the urban economic market and the infrastructure market. An agenda for reform in the road investment industry was also proposed. The study clearly identifies the relationship between road infrastructure investment and economic development, and the proposed formula is an appropriate tool for a first-order priority system. / Transport Economics, Logistics and Tourism / D. Com. (Transport Economics)

Financial liberalisation, through increasing investment as well as the average productivity of capital, should stimulate economic growth, or so the theory goes. Bank lending unfortunately suffers adverse selection and moral hazard effects, to which the establishment and expansion of stock markets has been offered as a remedy. However, research from developing country stock markets have shown that in many cases these markets did not complement the effects of credit market liberalisation but in rather important aspects subverted them. Countries that implemented credit market liberalisation and raised real interest rates only increased the price of debt capital rather than all capital. This caused a share price boom in many of them. When the price of equity capital fell it seriously undermined and indeed allowed large private corporations to skip altogether the main channel of high interest rates through which the theoretical McKinnon-Shaw effects were to operate. This study asks the research question of what effect the expansion of the South African stock exchange has had for its economic development. It makes use of a general empirical model to explain the relationship between financial development and real output. The model comprises indicators for growth, banking system development, stock market volatility; and, stock market development through a conglomerate index that accounts for market size, liquidity and integration with world capital markets. Quarterly data from 1989 to 2001 is analysed based on the null hypothesis that, as far as financial architecture is concerned, the development of the JSE Securities Exchange has stimulated the country's economic growth. This study found a negative and statistically significant relation between stock market development and economic growth. It suggests that while the JSE Securities Exchange is a relatively large stock market it is the presence of thin trading that prevents the proposed benefits of market development from accruing to the economy. Thus the hypothesis is rejected. However, since the only stable cointegrating vector is between growth and banking sector development, it recommends that by expanding their universal banking functions, the present banking structure, though oligopolistic, may be better suited to act as a catalyst for growth. / Business Management / D. Comm.

This dissertation examines the causal relationship between inward foreign direct investment (FDI) and economic growth (GDP) in SADC countries. The study investigates, within a panel data context, whether causation is short-term, long-term or both; and explores whether the causal relationship between the two variables differs according to income level. The study covered a panel of 15 SADC countries over the period 1980-2012. In order to assess whether the causal relationship between FDI inflows and economic growth is dependent on the level of income, the study divided the SADC countries into two groups, namely, the low-income and the middleincome countries. The study used the recently developed panel data analysis methods to examine this causal relationship. It adopted a three stage approach, which consists of panel unit root, panel cointegration and Granger causality to examine the dynamic causal relationship between the two variables. Panel unit root results show that both variables in the two SADC country groups were integrated of order one. Panel cointegration tests showed that the variables for low-income country group were not cointegrated, while the variables for the middle-income countries were cointegrated. Since the low-income country group panels were not cointegrated, Grangercausality tests were conducted within a VAR framework, while causality tests for the middleincome country group were conducted within an ECM framework. Panel Granger causality results for the low-income countries showed no evidence of causality in either direction. However, for the middle-income countries’ panel, there was evidence of a unidirectional causal flow from GDP to FDI in both the long- and short- run. The study concludes that the FDI-led growth hypothesis does not apply to SADC countries. The results imply that the recent high economic growth rates recorded in the SADC region, especially middle-income countries, have been attracting FDI. In other words, it is economic growth that drives FDI inflows into the SADC region, and not vice versa. These findings have profound policy implications for the SADC region at large and individual countries. / Economics / MCOM (Economics)

Using 1980 - 2012 annual data, the study empirically investigates the dynamic relationship between financial development and economic growth in three developing countries (South Africa, Brazil and Kenya) and three developed countries (United States of America, United Kingdom and Australia). The study was motivated by the current debate regarding the role of financial development in the economic growth process, and their causal relationship. The debate centres on whether financial development impacts positively or negatively on economic growth and whether it Granger-causes economic growth or vice versa. To this end, two models have been used. In Model 1 the impact of bank- and market-based financial development on economic growth is examined, while in Model 2 it is the causality between the two that is explored. Using the autoregressive distributed lag (ARDL) bounds testing approach to cointegration and error-correction based causality test, the results were found to differ from country to country and over time. These results were also found to be sensitive to the financial development proxy used. Based on Model 1, the study found that the impact of bank-based financial development on economic growth is positive in South Africa and the USA, but negative in the U.K – and neither positive nor negative in Kenya. Elsewhere the results were inconclusive. Market-based financial development was found to impact positively in Kenya, USA and the UK but not in the remaining countries. Based on Model 2, the study found that bank-based financial development Granger-causes economic growth in the UK, while in Brazil they Granger-cause each other. However, in South Africa, Kenya and USA no causal relationship was found. In Australia the results were inconclusive. The study also found that in the short run, market-based financial development Granger-causes economic growth in the USA but that in South Africa and Brazil, the reverse applies. On the other hand bidirectional causality was found to prevail in Kenya in the same period. / Economics / DCOM (Economics)

Le lien de causalité est une condition centrale du droit de la responsabilité administrative. Entre la faute et le préjudice, l’examen du lien de causalité est un impératif de justice et une inévitable exigence intellectuelle. Il permet de donner un ordre à la fois rationnel et juste aux faits. Réputé impénétrable, suspect d’arbitraire, acculé à un prétendu déclin par le développement de la logique assurantielle, le lien de causalité n’a pas fait l’objet d’une étude d’ensemble en droit public. L’analyse de la notion de lien de causalité permet pourtant de tromper cette image. Elle révèle, d’abord, qu’il faut distinguer le problème -métaphysique- de la causalité, de la question -pragmatique- de l’explication causale. La nature des problèmes posés par ces deux questions est différente ; celle qui se pose au juge est modeste : donner une explication rationnelle aux faits, sans quête de la vérité. Elle permet, ensuite, d’observer que le lien de causalité, s’il ne relève pas d’un constat objectif des faits, n’est toutefois pas empreint d’une subjectivité singulière par rapport à d’autres notions indéterminées en droit. L’étude de la pratique du lien de causalité en atteste. Le juge administratif a une approche ordonnée du lien de causalité fondée sur un équilibre entre attachement à la matérialité des faits et finalité de l’explication causale. Dans l’identification d’une cause, la hiérarchisation d’une pluralité de causes ou la circonscription du dommage, la jurisprudence administrative se caractérise par cette liberté, fidèle à l’arrêt Blanco, dans la détermination d’une politique jurisprudentielle, que le lien de causalité permet, parfois, mais suit seulement, le plus souvent. / Causal relationship is a central term in the law of administrative responsibility. Between fault and prejudice, the examination of causal relationship is an essential element of justice and constitutes an unavoidable intellectual requirement. It allows the judge to give an order which is both rational and just to facts. Reputed to be impenetrable, suspected of arbitrariness, driven into alleged decline by the development of the logic of insurance, causal relationship has never formed the object of a full-fledged study in public law. The analysis of the notion of causal relationship allows us to correct the image above. It first reveals that we have to distinguish the metaphysical problem of causality from the pragmatic question of causal explanation. The nature of the problem posed by these two questions is different. The question that is put to the judge is modest : give a rational explanation to facts without looking for the truth. It secondly allows to observe that the causal relationship, if it does not come close to being an objective observation of facts, does not bear the imprint of a specific subjectivity with regard to other indeterminate notions in law. The study of the practice of causal relationship bears witness to this. The administrative judge has an ordered approach of the causal relationship founded on a balance between attachment to the materiality of facts and the finality of causal explanation. In the identification of a cause, in the prioritization of multiple causes or in fixing damages, administrative jurisprudence is characterized by this freedom, which is in conformity with the Blanco ruling, in the determination of a jurisprudential policy that causal relationship sometimes renders possible, but which it only follows most often.

Das vorliegende Buch stellt eine überarbeitete und deutlich erweiterte zweite Ausgabe meines gleichnamigen Buches von 2012 dar. Es wendet sich in Form eines Lehrbuchs sowohl an Anfänger wie Fortgeschrittene der Wissenschaftstheorie sowie an Wissenschaftler, die sich dafür interessieren, wann Daten eine bestimmte Theorie begründen und wie stark die Bestätigung der Theorie durch die Daten ist. Im Vordergrund steht dabei immer die erkenntnistheoretische Frage, ob bestimmte Begründungsverfahren die Ziele der Wissenschaften in überzeugender Weise verfolgen oder ob es dagegen substantielle Einwände gibt. Leider wird sich herausstellen, dass kein Verfahren ohne Fehl und Tadel ist, und wir sollten die Schwächen unserer Begründungsverfahren genau kennen, um sie korrekt einsetzen zu können.

This dissertation examines the causal relationship between inward foreign direct investment (FDI) and economic growth (GDP) in SADC countries. The study investigates, within a panel data context, whether causation is short-term, long-term or both; and explores whether the causal relationship between the two variables differs according to income level. The study covered a panel of 15 SADC countries over the period 1980-2012. In order to assess whether the causal relationship between FDI inflows and economic growth is dependent on the level of income, the study divided the SADC countries into two groups, namely, the low-income and the middleincome countries. The study used the recently developed panel data analysis methods to examine this causal relationship. It adopted a three stage approach, which consists of panel unit root, panel cointegration and Granger causality to examine the dynamic causal relationship between the two variables. Panel unit root results show that both variables in the two SADC country groups were integrated of order one. Panel cointegration tests showed that the variables for low-income country group were not cointegrated, while the variables for the middle-income countries were cointegrated. Since the low-income country group panels were not cointegrated, Grangercausality tests were conducted within a VAR framework, while causality tests for the middleincome country group were conducted within an ECM framework. Panel Granger causality results for the low-income countries showed no evidence of causality in either direction. However, for the middle-income countries’ panel, there was evidence of a unidirectional causal flow from GDP to FDI in both the long- and short- run. The study concludes that the FDI-led growth hypothesis does not apply to SADC countries. The results imply that the recent high economic growth rates recorded in the SADC region, especially middle-income countries, have been attracting FDI. In other words, it is economic growth that drives FDI inflows into the SADC region, and not vice versa. These findings have profound policy implications for the SADC region at large and individual countries. / Economics / M. Com. (Economics)

Esta tese examina o problema de detecção de conectividade entre séries temporais no sentido de Granger no caso em que a natureza não linear das interações não permite sua determinação por meio de modelos auto-regressivos lineares vetoriais. Mostra-se que é possível realizar esta detecção com auxílio dos chamados métodos de Kernel, que se tornaram populares em aprendizado por máquina (\'machine learning\') já que tais métodos permitem definir formas generalizadas de teste de Granger, coerência parcial direcionada e função de transferência direcionada. Usando simulações, mostram-se alguns exemplos de detecção nos quais fica também evidente que resultados assintóticos deduzidos originalmente para estimadores lineares podem ser generalizados de modo análogo, mostrando-se válidos no presente contexto kernelizado. / This work examines the connectivity detection problem between time series in the Granger sense when the nonlinear nature of interactions determination is impossible via linear vector autoregressive models, but is, nonetheless, feasible with the aid of the so-called Kernel methods that are popular in machine learning. The kernelization approach allows defining generalised versions for Granger tests, partial directed coherence and directed transfer function, which the simulation of some examples shows that the asymptotic detection results originally deducted for linear estimators, can also be employed under kernelization if suitably adapted.

The study examines the dynamic relationship between financial development and investment in three Southern African countries (Botswana, South Africa and Mauritius) during the period 1976 – 2014 using annual data. The motivation for selecting these countries is mainly based on their different characteristics in their economic and financial structure. Employing the Autoregressive Distributed Lag (ARDL) bounds test approach, the study examines the role of financial development in boosting investment; and the causal relationship between financial development and investment. The study makes use of composite financial development indices and divides financial development into bank-based and market-based financial development. In addition, both the impact of bank- and market-based financial development on investment, on the one hand; and the causality between bank- and market-based financial development and investment, on the other, were examined within the flexible accelerator model/framework. For both models, both bank-based and market-based financial development are assumed as having an accelerator-enhancing effect on investment. Empirical results show that, for Botswana, the impact of bank-based financial development on investment is positive in both the short run and the long run while no impact of market-based financial development is found for both periods. For South Africa, the effect of bank-based financial development on investment is found to be negative in the short run and has no impact in the long run. However, market-based financial development has only a positive effect on investment in the long run. For Mauritius, market-based financial development is the only type of financial development found to have a significant positive effect on investment, and only, in the short run. The results of the causality test show that: for Mauritius, both bank-based and market-based financial development tend to drive investment, both in the short run and in the long run; while- in South Africa, investment drives both bank-based and market-based financial development only in the short run. In Botswana, bank-based and market-based financial development and investment drive each other in the short run while investment tends to only drive bank-based financial development in the long run. Therefore, all three countries show differing results and tend to confirm that there are inter-country differences that determine the relationship between investment and financial development. The inter-country differences maybe as a result of the different stages of financial and economic development for each country. / Economics / D. Phil. (Economics)