The initiative by the EU to combat global warming through the introduction of a cap-and-trade system for greenhouse gas emissions in 2005, known as the EU Emissions Trading System (ETS), resulted in the inception of a new financial market. The right to emit one tonne of CO2-equivalents, as well as derivatives on this right, have become commodities, traded both through exchanges and over the counter. A relevant question thus becomes how a market maker trading these derivatives should hedge their exposures. This thesis examines how stochastic optimisation can be used to hedge a portfolio of futures, forwards, and emissions rights in the EU ETS, while taking into account market microstructre effects such as transaction costs. This is done through the implementation of a Stochastic Programming (SP) model that weights portfolio risk against transaction costs,where the entire term structure of futures is Monte Carlo-simulated. The term structure of the futures is analysed by decomposing futures prices into the spot price, the term structure of the risk free interest rate, and the term structure of the convenience yield, as was first done by Working (1948). These are estimated using the non-parametric optimisation framework of Blomvall (2017), where EUROIS contracts and ICE EUA futures are used as benchmark instruments. It was found that the method results in smooth yield curves with small repricing errors, thanks to suitable parameter calibration through 3-fold Cross Validation for both curves. From day-to-day changes in the resulting curves, three systematic risk factors for each curve, that capture more than 98% of the variance during the analysed period from October 2012 to March 2018, were found with PCA. These factors were then fitted to univariate GARCH-models, and normal mixture copulas. This model allows for the hedging problem to be solved with SP. For the out-of-sample period from March 2018 to April 2022, the results show promise, as the portfolios hedged with SP are considerably less volatile than both a statically hedged and an unhedged portfolio. Furthermore, for some values of the parameter weighting risk and costs, these portfolios yield mean variance efficiency.

Cette thèse porte sur la prédiction de la détresse financière et son impact sur le rendement des actions. L’objet principal de cette thèse est de : (i) prédire la détresse financière des petites et moyennes entreprises françaises en utilisant plusieurs spécifications économétriques tels que, le modèle Logit, les réseaux de neurones artificiels, la méthode SVM et la régression des moindres carrés partiels, et (ii) d’identifier les facteurs de risque de détresse financière à caractère systématique, explicatifs des rendements des actions, et additionnels au modèle de Fama et French (1993) tels que le momentum, la détresse relative, la liquidité et la Value-at-Risk, sur le marché boursier Français. Cette étude comporte deux parties. La première partie, composée de 2 chapitres, s’interroge sur les principaux indicateurs discriminants entre les petites et moyennes entreprises françaises saines et celles en détresse financière un an et deux ans avant la défaillance. Elle mobilise différentes approches de prédiction et aboutit à des résultats empiriques qui font l’objet d’analyse. La deuxième partie, composée aussi de 2 chapitres, étudie le pouvoir explicatif, du modèle de Fama et French (1993) augmenté de certains facteurs de risque, mais aussi des modèles alternatifs à cette approche dans le contexte français. Les tests portent aussi sur le caractère systématique des facteurs de risque additionnels ou alternatifs, explicatifs des rendements des actions. Les résultats empiriques obtenus font l’objet d’analyse et permettent de proposer des implications managériales aux décideurs. / This thesis focuses on financial distress and its impact on stock returns. The main goal of this dissertation is: (i) to predict the financial distress of French small and medium-sized firms using a number of techniques namely Logit model, Artificial Neural Networks, Support Vector Machine techniques, and Partial Least Squares, and (ii) to identify the systematic risk factors of financial distress that can explain stock returns, in addition to those of Fama and French (1993) such as the momentum, the relative distress, the liquidity, and the Value-at-Risk in the French stock market. This study has been concretized in two parts. The first part, composed of 2 chapters, wonders about the main indicators that can discriminate between distressed and non-distressed French small and medium-sized firms one and two years before default. It mobilizes different prediction techniques and leads to the empirical results that are the subject of the analysis. The second part, composed also of 2 chapters, investigates the explanatory power of Fama and French (1993) model augmented by a number of risk factors, as well as alternative models in the French context. The tests also focus on the systematic nature of the additional or alternative risk factors, explaining the stock returns. The obtained empirical results are analyzed and propose managerial implications to decision makers.

Die studie vergelyk die prestasie van 'n koop-en-hou-strategie met die van 'n tydsberekeningstrategie binne die raamwerk van die arbitrasie-prysbepalingsteorie (APT) op die nywerheidsindeks van die Johannesburgse Aandelebeurs (JA). Die periode van die studie is oor twee tydperke, naamlik Januarie 1970 tot September 1987 en Januarie 1989 tot Junie 1997. Die langtermyntendens van die nywerheidsindeks en APT-faktore is bepaal deur die beste nie-reglynige model vir elke tydreeks te vind. Reglynige meervoudige stapsgewyse regressie-ontleding is gebruik om die bewegings van die nywerheidsindeks rondom die langtermyntendens te voorspel. Die sloeringsreekse van die langtermyntendensresidutelling van die APT-faktore en die sloeringsreekse van die eerste-ordeverskiltelling van die langtermyntendensresidutelling is as moontlike voorspellers gebruik. Gegrond hierop is beslissingslyne ontwik:kel wat gebruik is vir die implementering van 'n tydsberekeningstrategie. Die resultate van die studie is die volgende: • Waar die sloeringsreekse van die langtermyntendensresidutelling van die APTfaktore as moontlike voorspellers gebruik is, is die risiko-aangepaste opbrengskoers van 'n tydsberekeningstrategie 6, 41 persent en 0, 71 persent b6 die van 'n koop-en-hou-strategie vir tydperk een en twee onderskeidelik. • Waar die sloeringsreekse van die eerste-ordeverskiltelling van die langtermyntendensresidutelling van die APT-faktore as moontlike voorspellers gebruik is, is die risiko-aangepaste opbrengskoers van 'n tydsberekeningstrategie 10,40 persent en 1,04 persent b6 die van 'n koop-enhou- strategie vir tydperk een en twee onderskeidelik. Die belangrikste gevolgtrekking van die studie is dat die APT en 'n tydsberekeningstrategie teoreties en prakties versoenbaar is op die JA. Aanbevelings vir toekomstige navorsing is die volgende: ( 1) sistematiese risikofaktore, anders as makro-ekonomiese faktore, behoort identifiseer te word wat die voorspellingswaarde van die faktore in die tweede tydperk van die studie kan verhoog; (2) elke stap van die model wat ontwikkel is, behoort op elke indeks van die JA toegepas te word om die risiko-aangepaste opbrengskoers van 'n tydsberekeningstrategie toegepas op elkeen van die indekse met die van 'n koop-en-hou-strategie te vergelyk; en (3) die invloed van transaksiekoste en dividende op die potensiele voordele van tydsberekening moet bepaal word. / The study compares the performance of a buy-and-hold strategy with that of a markettiming strategy in the framework of the arbitrage pricing theory (APT) applied to the industrial index of the Johannesburg Stock Exchange (JSE). The study period is divided into two parts, namely January 1970 to September 1987 and January 1989 to June 1997. The long-term trend of the industrial index and every APT factor is determined by finding the best nonlinear model for each time series. Linear multiple stepwise regression analysis, with the lagged time series of the long-term trend error terms of the APT factors, is used to forecast the movement of the industrial index around its long-term trend. Decision lines were developed to implement a market-timing strategy. The results of the study are as follows: • Where the lagged time series of the long-term trend error terms of the APT factors were used as possible predictors, the risk-adjusted return of a markettiming strategy was 6, 41 percent and 0, 71 percent higher than that of a buyand- hold strategy for periods one and two respectively. • Where the lagged time series of the first-order difference of the long-term trend error term of the APT factors were used as possible predictors, the riskadjusted return of the market-timing strategy was 10,40 percent and 1,04 percent higher than that of a buy-and-hold strategy for periods one and two respectively. The main conclusion of the study is that the APT and a market-timing strategy are theoretically and practically reconcilable on the JSE. The main recommendations of the study are the following: (1) systematic risk factors, other than macroeconomic factors, should be identified in order to increase the forecasting value of these factors in the second period of the study; (2) each step of the model developed in this study should be repeated on every index of the JSE; and (3) the influence of transaction costs and dividends on the potential benefits of a market-timing strategy should be determined. / Business Management / DCom (Sakebestuur)

Die studie vergelyk die prestasie van 'n koop-en-hou-strategie met die van 'n tydsberekeningstrategie binne die raamwerk van die arbitrasie-prysbepalingsteorie (APT) op die nywerheidsindeks van die Johannesburgse Aandelebeurs (JA). Die periode van die studie is oor twee tydperke, naamlik Januarie 1970 tot September 1987 en Januarie 1989 tot Junie 1997. Die langtermyntendens van die nywerheidsindeks en APT-faktore is bepaal deur die beste nie-reglynige model vir elke tydreeks te vind. Reglynige meervoudige stapsgewyse regressie-ontleding is gebruik om die bewegings van die nywerheidsindeks rondom die langtermyntendens te voorspel. Die sloeringsreekse van die langtermyntendensresidutelling van die APT-faktore en die sloeringsreekse van die eerste-ordeverskiltelling van die langtermyntendensresidutelling is as moontlike voorspellers gebruik. Gegrond hierop is beslissingslyne ontwik:kel wat gebruik is vir die implementering van 'n tydsberekeningstrategie. Die resultate van die studie is die volgende: • Waar die sloeringsreekse van die langtermyntendensresidutelling van die APTfaktore as moontlike voorspellers gebruik is, is die risiko-aangepaste opbrengskoers van 'n tydsberekeningstrategie 6, 41 persent en 0, 71 persent b6 die van 'n koop-en-hou-strategie vir tydperk een en twee onderskeidelik. • Waar die sloeringsreekse van die eerste-ordeverskiltelling van die langtermyntendensresidutelling van die APT-faktore as moontlike voorspellers gebruik is, is die risiko-aangepaste opbrengskoers van 'n tydsberekeningstrategie 10,40 persent en 1,04 persent b6 die van 'n koop-enhou- strategie vir tydperk een en twee onderskeidelik. Die belangrikste gevolgtrekking van die studie is dat die APT en 'n tydsberekeningstrategie teoreties en prakties versoenbaar is op die JA. Aanbevelings vir toekomstige navorsing is die volgende: ( 1) sistematiese risikofaktore, anders as makro-ekonomiese faktore, behoort identifiseer te word wat die voorspellingswaarde van die faktore in die tweede tydperk van die studie kan verhoog; (2) elke stap van die model wat ontwikkel is, behoort op elke indeks van die JA toegepas te word om die risiko-aangepaste opbrengskoers van 'n tydsberekeningstrategie toegepas op elkeen van die indekse met die van 'n koop-en-hou-strategie te vergelyk; en (3) die invloed van transaksiekoste en dividende op die potensiele voordele van tydsberekening moet bepaal word. / The study compares the performance of a buy-and-hold strategy with that of a markettiming strategy in the framework of the arbitrage pricing theory (APT) applied to the industrial index of the Johannesburg Stock Exchange (JSE). The study period is divided into two parts, namely January 1970 to September 1987 and January 1989 to June 1997. The long-term trend of the industrial index and every APT factor is determined by finding the best nonlinear model for each time series. Linear multiple stepwise regression analysis, with the lagged time series of the long-term trend error terms of the APT factors, is used to forecast the movement of the industrial index around its long-term trend. Decision lines were developed to implement a market-timing strategy. The results of the study are as follows: • Where the lagged time series of the long-term trend error terms of the APT factors were used as possible predictors, the risk-adjusted return of a markettiming strategy was 6, 41 percent and 0, 71 percent higher than that of a buyand- hold strategy for periods one and two respectively. • Where the lagged time series of the first-order difference of the long-term trend error term of the APT factors were used as possible predictors, the riskadjusted return of the market-timing strategy was 10,40 percent and 1,04 percent higher than that of a buy-and-hold strategy for periods one and two respectively. The main conclusion of the study is that the APT and a market-timing strategy are theoretically and practically reconcilable on the JSE. The main recommendations of the study are the following: (1) systematic risk factors, other than macroeconomic factors, should be identified in order to increase the forecasting value of these factors in the second period of the study; (2) each step of the model developed in this study should be repeated on every index of the JSE; and (3) the influence of transaction costs and dividends on the potential benefits of a market-timing strategy should be determined. / Business Management / DCom (Sakebestuur)

Notre thèse consiste à expliquer, en apportant quelques éléments théoriques, les imperfections des stress tests macro-prudentiels d’EBA/BCE, et de proposer une nouvelle méthodologie de leur application ainsi que deux stress tests spécifiques en complément. Nous montrons que les stress tests macro-prudentiels peuvent être non pertinents lorsque les deux hypothèses fondamentales du modèle de base de Gordy-Vasicek utilisé pour évaluer le capital réglementaire des banques en méthodes internes (IRB) dans le cadre du risque de crédit (portefeuille de crédit asymptotiquement granulaire et présence d’une seule source de risque systématique qui est la conjoncture macro-économique), ne sont pas respectées. Premièrement, ils existent des portefeuilles concentrés pour lesquels les macro-stress tests ne sont pas suffisants pour mesurer les pertes potentielles, voire inefficaces si ces portefeuilles impliquent des contreparties non cycliques. Deuxièmement, le risque systématique peut provenir de plusieurs sources ; le modèle actuel à un facteur empêche la répercussion propre des chocs « macro ».Nous proposons un stress test spécifique de crédit qui permet d’appréhender le risque spécifique de crédit d’un portefeuille concentré, et un stress test spécifique de liquidité qui permet de mesurer l’impact des chocs spécifiques de liquidité sur la solvabilité de la banque. Nous proposons aussi une généralisation multifactorielle de la fonction d’évaluation du capital réglementaire en IRB, qui permet d’appliquer les chocs des macro-stress tests sur chaque portefeuille sectoriel, en stressant de façon claire, précise et transparente les facteurs de risque systématique l’impactant. Cette méthodologie permet une répercussion propre de ces chocs sur la probabilité de défaut conditionnelle des contreparties de ces portefeuilles et donc une meilleure évaluation de la charge en capital de la banque. / Our thesis consists in explaining, by bringing some theoretical elements, the imperfections of EBA / BCE macro-prudential stress tests, and proposing a new methodology of their application as well as two specific stress tests in addition. We show that macro-prudential stress tests may be irrelevant when the two basic assumptions of the Gordy-Vasicek core model used to assess banks regulatory capital in internal methods (IRB) in the context of credit risk (asymptotically granular credit portfolio and presence of a single source of systematic risk which is the macroeconomic conjuncture), are not respected. Firstly, they exist concentrated portfolios for which macro-stress tests are not sufficient to measure potential losses or even ineffective in the case where these portfolios involve non-cyclical counterparties. Secondly, systematic risk can come from several sources; the actual one-factor model doesn’t allow a proper repercussion of the “macro” shocks. We propose a specific credit stress test which makes possible to apprehend the specific credit risk of a concentrated portfolio, as well as a specific liquidity stress test which makes possible to measure the impact of liquidity shocks on the bank’s solvency. We also propose a multifactorial generalization of the regulatory capital valuation model in IRB, which allows applying macro-stress tests shocks on each sectorial portfolio, stressing in a clear, precise and transparent way the systematic risk factors impacting it. This methodology allows a proper impact of these shocks on the conditional probability of default of the counterparties of these portfolios and therefore a better evaluation of the capital charge of the bank.