A mixed integer linear programming formulation is used to solve the problem of allocating assets from a bank to its counterparties as collateral within securities lending. The aim of the optimisation is to reduce the cost of allocated collateral, which is broken down into the components opportunity cost, counterparty risk cost and triparty cost. A solution consists of transactions to carry out to improve the allocation cost, each transaction consisting of sending a quantity of some asset from a portfolio to the bank or from the bank to some portfolio. The optimisation process is split into subproblems to separate obvious transactions from more complex optimisations. The reduction of each cost component is examined for all the subproblems. Two subproblems transform an initial collateral allocation into a feasible one which is then improved by the optimisation. Decreasing opportunity cost is shown to be an easier task than decreasing counterparty risk and triparty costs since the latter costs require a comparatively large number of transactions. The optimisation is run several times in a row, performing the suggested transactions after each solved iteration. The cost reduction of k optimisation iterations with 10 transactions per iteration is shown to be similar to the cost reduction of 1 optimisation iteration with 10k transactions. The solution time increases heavily with the number of iterations. The suggested transactions may need to be performed in a certain order. A precedence constrained problem takes this into account. The problem is large and the execution time is slow if a limit is imposed on the number of allowed transactions. A strategic selection of portfolios can limit the number of suggested transactions and still reach a solution which comes close to the optimal one. This can also be done by requiring that all suggested transactions must reduce the cost by a minimum amount. The final model is ready to be used in a semi-automatic fashion, where transactions are verified by a human who checks if they are sound. A fully automated process requires further testing on historical and recent data. / Ett blandat-heltal linjärt optimeringsproblem används för att lösa uppgiften att tilldela värdepapper från en bank till dess kunder som pant för värdepapperslån. Målet med optimeringen är att minska kostnaden av den tilldelade panten. Kostnaden bryts ned i komponenterna alternativkostnad, motpartsrisk och tripartykostnad. En lösning består av föreslagna transaktioner som ska genomföras för att förbättra den nuvarande säkerhetstilldelningens kostnad. En transaktion består av att ta hem eller skicka ut en kvantitet av ett visst värdepapper från eller till en av bankens kunders portföljer. Optimeringsproblemet bryts ned i flera delproblem med syfte att särskilja uppenbara föreslagna säkerheter till en godkänd tildelning som sedan blir en startpunkt för optimeringen. Att minska alternativkostnad visar sig vara enklare än att minska motpartsrisk och tripartykostnader på så sätt att de sistnämnda kostnaderna kräver fler transaktioner för att minskas. Optimeringen körs flera gånger i rad, där alla föreslagna transaktioner från en iteration genomförs innan nästa iteration körs. Kostnadsminskningen av k körningar med 10 transaktioner visar sig vara väldigt nära, om än något mindre, än en körning med 10k transaktioner. Exekveringstiden ökar drastiskt med antalet iterationer. De föreslagna transaktionerna kan behöva genomföras i en viss ordning. En problemformulering konstrueras som tar höjd för detta, men exekveringstiden är extremt lång när antalet transaktioner begränsas. Ett strategiskt urval av portföljer kan begränsa antalet föreslagna transaktioner utan att försämra lösningen särskilt mycket. På ett liknande sätt kan antalet föreslagna transaktioner minskas genom att lägga till ett villkor som säger att lönsamheten av en transaktion måste överskrida en given minsta tröskel. Den slutgiltiga modellen är redo att användas om de föreslagna transaktionerna granskas manuellt innan de genomförs. En helt automatisk process ligger längre fram i tiden efter ytterligare tester på historisk och nuvarande data.

The financial stability of the insurers is important to fulfil its role as a risk transfer mechanism and to protect the purchasers of their products. The European Union is introducing the Solvency II to modernise the current Solvency I regime and to harmonise the different insurance legislation of the members of the European Union. Solvency II introduces an architecture consisting of three pillars, with Pillar I setting the solvency capital requirements, Pillar II the governance and risk management requirements and Pillar III the reporting requirements. The South African Regulator initiated Solvency Assessment and Management for implementation in 2016 to align the South African prudential regulatory framework to meet the Solvency II requirements for third country equivalence. The problem that this study addressed is the possible effect that the introduction of Solvency Assessment and Management may have on the sustainability of short-term insurers in South Africa. The results of a empirical component of the study indicated that small and medium short-term insurers may be negatively impacted due to the costs incurred to implement and comply with the requirements of the new regulatory framework. The effect on the South African short-term industry can be that cover is concentrated among a few large short-term insurers. / Business Management / M. Com. (Business Management)

Suite à la crise financière de 2008 les pays du G20 se sont interrogés sur la transparence des marchés, la stabilité du système et une façon de réguler les risques posés par le nouvel environnement économique. Les produits dérivés de gré à gré ont été identifiés et des engagements ont été pris en faveur de nouvelles régulations des dérivés de gré à gré et la gestion des risques sous-jacents. Les régulateurs ont donc adopté chacun à leur tour un cadre législatif régulant les dérivés de gré à gré tout en déployant un effort international d'harmonisation et de reconnaissance des contreparties assujetties à des régimes équivalents. Les autorités canadiennes en valeurs mobilières ont publié des projets de règlements. Nous nous interrogerons sur ce nouveau cadre réglementaire des dérivés de gré à gré élaboré par les autorités canadiennes en valeurs mobilières, prenant en considération les spécificités canadiennes et les acteurs actifs sur leur territoire. Notre étude traite de ces projets de règlements et de la difficulté d'encadrer les marchés des dérivés de gré à gré qui par définition ne comportent pas de plateformes de négociation ou de lieu géographique et de frontières mais se caractérisent surtout par le lien contractuel entre les parties et l'identification de ces parties. L'élaboration d'un nouveau cadre pour les dérivés de gré à gré qui régule les transactions transfrontières semble très délicat à traiter et les possibles conflits et chevauchements de lois seront inévitables. Confrontés à des définitions divergentes de contreparties locales, les parties à une opération seront condamnées à un risque de qualification en vertu des règlements nationaux sur les dérivés de gré à gré. Une concertation pourrait être renforcée et la détermination de l'autorité compétente ainsi que les concepts de contreparties locales, succursales ou filiales pourraient être harmonisés. / Having in mind the 2008 financial crisis the G20 countries have questioned the transparency of the markets, the stability of the system and explored new solutions in order to control the risks triggered by a new economic environment. OTC derivatives have been identified and commitments were made in favor of new regulations of OTC derivatives and the management of the underlying risks. Regulators have therefore adopted in turn a legislative framework regulating OTC derivatives while deploying an incentive for international harmonization and recognition of counterparties subject to equivalent schemes. Canadian Securities Administrators have issued proposed regulations. We wonder how the Canadian Securities Administrators have developed this new regulatory framework for OTC derivatives, taking into consideration the Canadian specificities and the local activities of the Canadian actors? Our study addresses these draft regulations and the difficulty to supervise OTC derivatives which in the past, were not traded via platforms, recorded or related to a geographic location but mainly characterized by the contractual relationship between the parties. The development of a new framework for OTC derivatives which will regulate cross-border transactions seem very difficult to deal with and possible conflicts and overlapping laws are inevitable. Faced with different definitions of local counterparts, the parties to a transaction will be condemned to a risk of qualification under national regulations of OTC derivatives. A dialogue shall therefore be strengthened and the determination of the competent authority and clarification of the local counterparts concepts, branches or subsidiaries shall be harmonized.

The financial stability of the insurers is important to fulfil its role as a risk transfer mechanism and to protect the purchasers of their products. The European Union is introducing the Solvency II to modernise the current Solvency I regime and to harmonise the different insurance legislation of the members of the European Union. Solvency II introduces an architecture consisting of three pillars, with Pillar I setting the solvency capital requirements, Pillar II the governance and risk management requirements and Pillar III the reporting requirements. The South African Regulator initiated Solvency Assessment and Management for implementation in 2016 to align the South African prudential regulatory framework to meet the Solvency II requirements for third country equivalence. The problem that this study addressed is the possible effect that the introduction of Solvency Assessment and Management may have on the sustainability of short-term insurers in South Africa. The results of a empirical component of the study indicated that small and medium short-term insurers may be negatively impacted due to the costs incurred to implement and comply with the requirements of the new regulatory framework. The effect on the South African short-term industry can be that cover is concentrated among a few large short-term insurers. / Business Management / M. Com. (Business Management)

Subprime residential mortgage loan securitization and its associated risks have been a major topic of discussion since the onset of the subprime mortgage crisis (SMC) in 2007. In this regard, the thesis addresses the issues of subprime residential mortgage loan (RML) securitization in discrete-, continuous-and discontinuous-time and their connections with the SMC. In this regard, the main issues to be addressed are discussed in Chapters 2, 3 and 4. In Chapter 2, we investigate the risk allocation choices of an investing bank (IB) that has to decide between risky securitized subprime RMLs and riskless Treasuries. This issue is discussed in a discrete-time framework with IB being considered to be regret- and risk-averse before and during the SMC, respectively. We conclude that if IB takes regret into account it will be exposed to higher risk when the difference between the expected returns on securitized subprime RMLs and Treasuries is small. However, there is low risk exposure when this difference is high. Furthermore, we assess how regret can influence IB's view - as a swap protection buyer - of the rate of return on credit default swaps (CDSs), as measured by the premium based on default swap spreads. We find that before the SMC, regret increases IB's willingness to pay lower premiums for CDSs when its securitized RML portfolio is considered to be safe. On the other hand, both risk- and regret-averse IBs pay the same CDS premium when their securitized RML portfolio is considered to be risky. Chapter 3 solves a stochastic optimal credit default insurance problem in continuous-time that has the cash outflow rate for satisfying depositor obligations, the investment in securitized loans and credit default insurance as controls. As far as the latter is concerned, we compute the credit default swap premium and accrued premium by considering the credit rating of the securitized mortgage loans. In Chapter 4, we consider a problem of IB investment in subprime residential mortgage-backed securities (RMBSs) and Treasuries in discontinuous-time. In order to accomplish this, we develop a Levy process-based model of jump diffusion-type for IB's investment in subprime RMBSs and Treasuries. This model incorporates subprime RMBS losses which can be associated with credit risk. Furthermore, we use variance to measure such risk, and assume that the risk is bounded by a certain constraint. We are now able to set-up a mean-variance optimization problem for IB's investment which determines the optimal proportion of funds that needs to be invested in subprime RMBSs and Treasuries subject to credit risk measured by the variance of IE's investment. In the sequel, we also consider a mean swaps-at-risk (SaR) optimization problem for IB's investment which determines the optimal portfolio which consists of subprime RMBSs and Treasuries subject to the protection by CDSs required against the possible losses. In this regard, we define SaR as indicative to IB on how much protection from swap protection seller it must have in order to cover the losses that might occur from credit events. Moreover, SaR is expressed in terms of Value-at-Risk (VaR). Finally, Chapter 5 provides an analysis of discrete-, continuous- and discontinuous-time models for subprime RML securitization discussed in the aforementioned chapters and their connections with the SMC. The work presented in this thesis is based on 7 peer-reviewed international journal articles (see [25], [44], [45], [46], [47], [48] and [55]), 4 peer-reviewed chapters in books (see [42], [50j, [51J and [52]) and 2 peer-reviewed conference proceedings papers (see [11] and [12]). Moreover, the article [49] is currently being prepared for submission to an lSI accredited journal. / Thesis (Ph.D. (Applied Mathematics))--North-West University, Potchefstroom Campus, 2010.

Subprime residential mortgage loan securitization and its associated risks have been a major topic of discussion since the onset of the subprime mortgage crisis (SMC) in 2007. In this regard, the thesis addresses the issues of subprime residential mortgage loan (RML) securitization in discrete-, continuous-and discontinuous-time and their connections with the SMC. In this regard, the main issues to be addressed are discussed in Chapters 2, 3 and 4. In Chapter 2, we investigate the risk allocation choices of an investing bank (IB) that has to decide between risky securitized subprime RMLs and riskless Treasuries. This issue is discussed in a discrete-time framework with IB being considered to be regret- and risk-averse before and during the SMC, respectively. We conclude that if IB takes regret into account it will be exposed to higher risk when the difference between the expected returns on securitized subprime RMLs and Treasuries is small. However, there is low risk exposure when this difference is high. Furthermore, we assess how regret can influence IB's view - as a swap protection buyer - of the rate of return on credit default swaps (CDSs), as measured by the premium based on default swap spreads. We find that before the SMC, regret increases IB's willingness to pay lower premiums for CDSs when its securitized RML portfolio is considered to be safe. On the other hand, both risk- and regret-averse IBs pay the same CDS premium when their securitized RML portfolio is considered to be risky. Chapter 3 solves a stochastic optimal credit default insurance problem in continuous-time that has the cash outflow rate for satisfying depositor obligations, the investment in securitized loans and credit default insurance as controls. As far as the latter is concerned, we compute the credit default swap premium and accrued premium by considering the credit rating of the securitized mortgage loans. In Chapter 4, we consider a problem of IB investment in subprime residential mortgage-backed securities (RMBSs) and Treasuries in discontinuous-time. In order to accomplish this, we develop a Levy process-based model of jump diffusion-type for IB's investment in subprime RMBSs and Treasuries. This model incorporates subprime RMBS losses which can be associated with credit risk. Furthermore, we use variance to measure such risk, and assume that the risk is bounded by a certain constraint. We are now able to set-up a mean-variance optimization problem for IB's investment which determines the optimal proportion of funds that needs to be invested in subprime RMBSs and Treasuries subject to credit risk measured by the variance of IE's investment. In the sequel, we also consider a mean swaps-at-risk (SaR) optimization problem for IB's investment which determines the optimal portfolio which consists of subprime RMBSs and Treasuries subject to the protection by CDSs required against the possible losses. In this regard, we define SaR as indicative to IB on how much protection from swap protection seller it must have in order to cover the losses that might occur from credit events. Moreover, SaR is expressed in terms of Value-at-Risk (VaR). Finally, Chapter 5 provides an analysis of discrete-, continuous- and discontinuous-time models for subprime RML securitization discussed in the aforementioned chapters and their connections with the SMC. The work presented in this thesis is based on 7 peer-reviewed international journal articles (see [25], [44], [45], [46], [47], [48] and [55]), 4 peer-reviewed chapters in books (see [42], [50j, [51J and [52]) and 2 peer-reviewed conference proceedings papers (see [11] and [12]). Moreover, the article [49] is currently being prepared for submission to an lSI accredited journal. / Thesis (Ph.D. (Applied Mathematics))--North-West University, Potchefstroom Campus, 2010.

Cette thèse se propose d’analyser la structure et la dynamique de dépendance de crédit des institutions financières aux Etats-Unis et en Europe durant la crise financière de 2008. Un premier chapitre présente une revue de la littérature des modèles multi-dimensionnels de crédit et des modèles économétriques de contagion financière. Ce chapitre a pour vocation de guider notre réflexion à la fois conceptuelle et méthodologique sur les hypothèses analytiques de la contagion ainsi que ses méthodes de mesure. Nous montrons que si la contagion est devenue une hypothèse centrale des modèles multivariés de risque de crédit, il n’en reste néanmoins que sa définition et sa quantification ne font pas l’objet de consensus dans la littérature. Un deuxième chapitre propose une analyse empirique des co-movements des rendements de CDS de banques et sociétés d’assurance américaines et européennes. La dissociation de leur structure de dépendance entre association linéaire et dépendances extrêmes nous permet de mettre en évidence des phénomènes d'interconnexions entre institutions financières apparues au courant de la crise et véhiculant ainsi sous l'effet de la contagion, un risque systémique croissant. Un dernier chapitre présente une interprétation économique des résultats obtenus dans notre deuxième chapitre. En particulier, nous cherchons à quantifier l'influence jouée par la contagion et les facteurs de risques communs sur la dynamique de dépendance extrême des institutions financières. Nous démontrons ainsi le rôle du risque de contrepartie, du risque de liquidité et du risque de défaut des institutions financières dans la transmission de la contagion sur le marché de CDS. / This thesis examines the credit dependence structure and dynamics of financial institutions in the U.S. and Europe amid the recent financial crisis. A first chapter presents a survey of multi-name models of credit risk and econometric models of financial contagion with the purpose of guiding both the analytical and conceptual assumptions and econometric modelling techniques we use in the subsequent chapters. We show that if contagion has become a central cornerstone of multi-name models of credit risk, there is nonetheless a lack of consensus on the way to both define and measure it. A second chapter presents the results of an empirical analysis of U.S. and European banks and insurance companies’ CDS return extreme co-movements. By uncovering financial institutions' linear as well as extremal dependence structures, we provide evidence that their credit dependence has strengthened during the crisis, thereby effectively conveying, in the face of extreme tail events, potential systemic risks. A third and last chapter provides an economic rationale of the results presented in our second chapter. In particular, we examine the impact of common risk factors and contagion on the dynamics of financial institutions' extremal credit dependence. We demonstrate the role of counterparty risk and liquidity risk, as well the repricing by market participants since July 2007 of their jump-to-default premia as additional channels driving financial institutions' increased dependence and amplifying contagion on the CDS market.

Cette Thèse de sciences de gestion, se propose d’élucider les difficultés que rencontrent les acteurs du système bancaire comorien et apporter des solutions afin de lui garantir sa solidité, stabilité et enfin sa pérennité. Elle est divisée en deux parties. La première porte plus particulièrement sur le cadre national et internationale du système bancaire comorien. La deuxième met en évidence les banques comoriennes confrontées à la transparence financière et aux exigences de supervision prudentielle. Le premier titre de la première partie, tâche à mettre en lumière l’organisation actuelle du système bancaire comorien inspiré du modèle français (chapitre 1) et l’apport du développement récent de la finance islamique (chapitre 2) afin de combler le retard de la banque conventionnelle. La réorganisation de la Banque Centrale des Comores et la mise en place de la banque islamique locale, peuvent contribuer au changement radical du système bancaire comorien. Le deuxième titre, permet au régulateur et prêteur en dernier ressort (Banque Centrale des Comores) de prendre le modèle des normes prudentielles internationales proposées par le Comité de Bâle (Bâle II et III), pour réguler le système bancaire comorien afin de lui garantir sa solidité, stabilité et enfin sa pérennité (chapitre 1). A travers ces recommandations du comité de Bâle, nous avons apporté des solutions en élaborant la Matrice Msahazi Credit Scoring Corporation, destinée aux analyses des données des banques comoriennes contre un risque endogène (Chapitre2). Nous avons aussi élaboré d’autres matrices que les banques comoriennes se serviront pour la notation interne, des risques de contreparties (entreprises et particuliers) afin de lutter contre le risque exogène. La deuxième partie de cette Thèse suggère deux autres solutions : la première est l’exigence de transparence financière des banques comoriennes (Pilier 3 : Bâle2 et 3) afin de lutter contre les malversations financières orchestrées par certains agents (titre I). Le premier chapitre introduit l’objectif de la communication financière de manière générale et la manière dont le comité de Bâle (Bâle 2 et 3) recommande les banques de communiquer leurs informations financières (méthodes d’évaluations des risques et fonds propres). Le deuxième chapitre propose aux banques comoriennes et aux autorités de contrôles, les techniques de notation financière pratiquées au niveau internationale pour distinguer le niveau de solvabilité de la contrepartie. La deuxième solution, nous avons donné à la Banque Centrale des Comores, des techniques pour renforcer la supervision prudentielle (Pilier 2, Bâle 2 et 3), (titre II). Le premier chapitre exige d’une part la direction et le conseil d’administration de la banque de définir les techniques de contrôles, d’indentifications, d’évaluations, gestions des risques et les objectifs de fonds propre à atteindre. D’autre part, l’autorité de contrôle (Banque centrale des Comores) doit passer au crible tous ces outils de contrôle. Au deuxième et dernier chapitre de la recherche, nous avons proposé à la Banque Centrale des Comores des nouvelles méthodes de supervision prudentielle afin de garantir la solidité, stabilité et pérennité du système bancaire. Nous avons l’espoir que l’ensemble de ces suggestions contribueront à préserver la solidité, stabilité et pérennité du système bancaire comorien afin de financer le développement de l’économie comorienne et sortir le pays de la pauvreté. / This thesis on busness management, aims to elucidate the difficulties faced by the stakeholders of the Comorian banking system and to provide solutions to ensure its soundness, stability and sustainability. The thesis is divided into two parts. The first focuses specifically on the national and international context of the Comorian banking system. The second, highlights how the Comorian banks should adapt to the financial transparency and prudential supervision requirements. The first title of the first part, tries toshed light on the current organization of the Comorian banking system based on the French model (Chapter 1) and the contribution of the recent development of Islamic finance (Chapter 2) to close the gap in conventional banking. The reorganization of the Central Bank of the Comoros and the establishment of the local Islamic bank can contribute to a radical change in the Comorian banking system. The second title allows the regulator and lender of last resort (Central Bank of the Comoros ) to take the model of international prudential standards proposed by the Basel Committee (Basel II and III) to regulate the Comorian banking system in order to guarantee its soundness, stability and finally sustainability (Chapter 1). Through these recommendations of the Basel committee, we have provided solutions by developing Msahazi Credit Scoring Matrix Corporation, intended to analyse data of Comorian banks against endogenous risk (Chapter 2). We have also developed matrices other than Comorian banks used for internal rating of the counterparty risk (companies and individuals) to fight against exogenous risk. The second part of this thesis suggests two alternatives: the first is the requirement of financial transparency for Comorian banks (Pillar 3: Basel Conventions 2 and 3) in order to fight against embezzlement orchestrated by certain agents (Title I). The first chapter introduces the objective of financial reporting in general, and how the Basel Committee (Basel 2 and 3) asks banks to disclose their financial information (methods of risk assessments and equity). The second chapter provides credit rating techniques practiced at international level to the Comorian banks and supervisory authorities in order to distinguish the level of creditworthiness of companies and clients concerned. The second alternative we have given to the Central Bank of the Comoros is the techniques for strengthening prudential supervision (Pillar 2, Basel 2 and 3), (Title II) . The first chapter requires both the management and the bank's board of directors to define control techniques, identifications, assessments, risk managements and core capital goals. On the other hand, the supervisory authority (Comoros Central Bank) has to go through all these control tools. In the second and final chapter of the research, we propose to the Central Bank of the Comoros new prudential supervision methods to ensure the soundness, stability and sustainability of the banking system. We hope that all of these suggestions will help to preserve the soundness, stability and durability of the Comorian banking system in order to finance the development of the Comorian economy and lift the country out of poverty.