The dissertation compares the export credit rating model of the national Export Guarantee and Insurance Agency EGAP with models applied by selected Czech banks. The first part of the dissertation presents a summary of credit risk theory. It depicts the main principles of lending and its risks. The dissertation further describes the factors that influence credit risk and the methods of its modelling. While mathematical risk models project the expected loss as well as its sensitivity to the risk factors, the focus of this thesis lies in qualitative models which set a normalized scale for probability of default, the so called credit rating models. The main contribution of the dissertation lies in the survey carried out among four Czech banks belonging to owners from various countries, from which we get an overview of their rating models. It follows from the gathered information that their models are based on financial indicators when rating the buyers/exporters. The models are also considerably amended by non-financial factors whose importance in certain cases rose following the recent financial crisis. The agency EGAP insures business activities abroad and therefore its model takes into account also specific factors related to the destination country. The main difference between the models of EGAP and the examined banks lies in the method of creation and validation: EGAP does not dispose of sufficient amount of business case studies, so that it has to rely on external consulting services when setting up and validating the model. The dissertation concludes that while all rating models are composed of similar risk factors highlighting past financial indicators of the financed business, each analysed rating model differs significantly in the specific database of business cases that were used to construct the model, depending on the availability of data to the bank/insurer. The conclusion that can be drawn from this fact is that the main factor for successful prevention of future failures of the credit rating models will be the extent of the credit assessment database which will be used for the construction of the respective rating model.

El risc de crèdit s'associa a l'eventual incompliment de les obligacions de pagament per part dels creditors. En aquest cas, l'interès principal de les institucions financeres és mesurar i gestionar amb precisió aquest risc des del punt de vista quantitatiu. Com a resposta a l'interès esmentat, aquesta tesi doctoral, titulada "Structural Credit Risk Models: Estimation and Applications", se centra en l'ús pràctic dels anomenats "models estructurals de risc de crèdit". Aquests models es caracteritzen perquè estableixen una relació explícita entre el risc de crèdit i diverses variables fonamentals, la qual cosa permet un ventall ampli d'aplicacions. Concretament, la tesi analitza el contingut informatiu tant del mercat d'accions com del mercat de CDS sobre la base dels models estructurals esmentats.El primer capítol, estudia la velocitat distinta amb què el mercat d'accions i el mercat de CDS incorporen nova informació sobre el risc de crèdit. L'anàlisi se centra a respondre dues preguntes clau: quin d'aquests mercats genera una informació més precisa sobre el risc de crèdit i quins factors determinen el diferent contingut informatiu dels indicadors respectius de risc, és a dir, les primes de crèdit implícites en el mercat d'accions enfront del de CDS. La base de dades utilitzada inclou 94 empreses (40 d'europees, 32 de nordamericanes i 22 de japoneses) durant el període 2002-2004. Entre les conclusions principals destaquen la naturalesa dinàmica del procés de price discovery, una interconnexió més gran entre ambdós mercats i un major domini informatiu del mercat d'accions, associat a uns nivells més elevats del risc de crèdit, i, finalment, una probabilitat més gran de lideratge informatiu del mercat de CDS en els períodes d'estrès creditici.El segon capítol se centra en el problema de l'estimació de les variables latents en els models estructurals. Es proposa una nova metodologia, que consisteix en un algoritme iteratiu aplicat a la funció de versemblança per a la sèrie temporal del preu de les accions. El mètode genera estimadors de pseudomàxima versemblança per al valor, la volatilitat i el retorn que s'espera obtenir dels actius de l'empresa. Es demostra empíricament que aquest nou mètode produeix, en tots els casos, valors raonables del punt de fallida. A més, aquest mètode és contrastat d'acord amb les primes de CDS generades. S'observa que, en comparació amb altres alternatives per fixar el punt de fallida (màxima versemblança estàndard, barrera endògena, punt d'impagament de KMV i nominal del deute), l'estimació per pseudomàxima versemblança proporciona menys divergències.El tercer i darrer capítol de la tesi tracta la qüestió relativa a components distints del risc de crèdit a la prima dels CDS. Més concretament, estudia l'efecte del desequilibri entre l'oferta i la demanda, un aspecte important en un mercat on el nombre de compradors (de protecció) supera habitualment el de venedors. La base de dades cobreix, en aquest cas, 163 empreses en total (92 d'europees i 71 de nord-americanes) per al període 2002- 2008. Es demostra que el desequilibri entre l'oferta i la demanda té, efectivament, un paper important a l'hora d'explicar els moviments a curt termini en els CDS. La influència d'aquest desequilibri es detecta després de controlar l'efecte de variables fonamentals vinculades al risc de crèdit, i és més gran durant els períodes d'estrès creditici. Aquests resultats il·lustren que les primes dels CDS reflecteixen no tan sols el cost de la protecció, sinó també el cost anticipat per part dels venedors d'aquesta protecció per tancar la posició adquirida. / El riesgo de crédito se asocia al potencial incumplimiento por parte de los acreedores respecto de sus obligaciones de pago. En este sentido, el principal interés de las instituciones financieras es medir y gestionar con precisión dicho riesgo desde un punto de vista cuantitativo. Con objeto de responder a este interés, la presente tesis doctoral titulada "Structural Credit Risk Models: Estimation and Applications", se centra en el uso práctico de los denominados "Modelos Estructurales de Riesgo de Crédito". Estos modelos se caracterizan por establecer una conexión explícita entre el riesgo de crédito y diversas variables fundamentales, permitiendo de este modo un amplio abanico de aplicaciones. Para ser más explícitos, la presente tesis explora el contenido informativo tanto del mercado de acciones como del mercado de CDS sobre la base de los mencionados modelos estructurales.El primer capítulo de la tesis estudia la distinta velocidad con la que el mercado de acciones y el mercado de CDS incorporan nueva información sobre el riesgo de crédito. El análisis se centra en contestar dos preguntas clave: cuál de estos mercados genera información más precisa sobre el riesgo de crédito, y qué factores determinan en distinto contenido informativo de los respectivos indicadores de riesgo, esto es, primas de crédito implícitas en el mercado de acciones frente a CDS. La base de datos utilizada engloba a 94 compañías (40 europeas, 32 Norteamericanas y 22 japonesas) durante el periodo 2002-2004. Entre las principales conclusiones destacan la naturaleza dinámica del proceso de price discovery, la mayor interconexión entre ambos mercados y el mayor dominio informativo del mercado de acciones asociados a mayores niveles del riesgo de crédito, y finalmente la mayor probabilidad de liderazgo informativo del mercado de CDS en los periodos de estrés crediticio.El segundo capítulo se centra en el problema de estimación de variables latentes en modelos estructurales. Se propone una nueva metodología consistente en un algoritmo iterativo aplicado a la función de verosimilitud para la serie temporal del precio de las acciones. El método genera estimadores pseudo máximo verosímiles para el valor, volatilidad y retorno esperado de los activos de la compañía. Se demuestra empíricamente que este nuevo método produce en todos los casos valores razonables del punto de quiebra. El método es además contrastado en base a las primas de CDS generadas. Se observa que, en comparación con otras alternativas para fijar el punto de quiebra (máxima verosimilitud estándar, barrera endógena, punto de impago de KMV, y nominal de la deuda), la estimación por pseudo máxima verosimilitud da lugar a las menores divergencias.El tercer y último capítulo de la tesis aborda la cuestión relativa a componentes distintos al riesgo de crédito en la prima de los CDS. Se estudia más concretamente el efecto del desequilibrio entre oferta y demanda, un aspecto importante en un mercado donde el número de compradores (de protección) supera habitualmente al de vendedores. La base de datos cubre en este caso un total de 163 compañías (92 europeas y 71 norteamericanas) para el periodo 2002-2008. Se demuestra que el desequilibrio entre oferta y demanda tiene efectivamente un papel importante a la hora de explicar los movimientos de corto plazo en los CDS. La influencia de este desequilibrio se detecta una vez controlado el efecto de variables fundamentales ligadas al riesgo de crédito, y es mayor durante los periodos de estrés crediticio. Estos resultados ilustran que las primas de los CDS reflejan no sólo el coste de la protección, sino el coste anticipado por parte de los vendedores de tal protección de cerrar la posición adquirida. / Credit risk is associated with potential failure of borrowers to fulfill their obligations. In that sense, the main interest of financial institutions becomes to accurately measure and manage credit risk on a quantitative basis. With the intention to respond to this task this doctoral thesis, entitled "Structural Credit Risk Models: Estimation and Applications", focuses on practical usefulness of structural credit risk models that are characterized with explicit link with economic fundamentals and consequently allow for a broad range of application possibilities. To be more specific, in essence, the thesis project explores the information on credit risk embodied in the stock market and market for credit derivatives (CDS market) on the basis of structural credit risk models. The issue addressed in the first chapter refers to relative informational content of stock and CDS market in terms of credit risk. The overall analysis is focused on answering two crucial questions: which of these markets provides more timely information regarding credit risk, and what are the factors that influence informational content of credit risk indicators (i.e. stock market implied credit spreads and CDS spreads). Data set encompasses international set of 94 companies (40 European, 32 US and 22 Japanese) during the period 2002-2004. The main conclusions uncover time-varying behaviour of credit risk discovery, stronger cross market relationship and stock market leadership at higher levels of credit risk, as well as positive relationship between the frequency of severe credit deterioration shocks and the probability of the CDS market leadership.Second chapter concentrates on the problem of estimation of latent parameters of structural models. It proposes a new, maximum likelihood based iterative algorithm which, on the basis of the log-likelihood function for the time series of equity prices, provides pseudo maximum likelihood estimates of the default barrier and of the value, volatility, and expected return on the firm's assets. The procedure allows for credit risk estimation based only on the readily available information from stock market and is empirically tested in terms of CDS spread estimation. It is demonstrated empirically that, contrary to the standard ML approach, the proposed method ensures that the default barrier always falls within reasonable bounds. Moreover, theoretical credit spreads based on pseudo ML estimates offer the lowest credit default swap pricing errors when compared to the other options that are usually considered when determining the default barrier: standard ML estimate, endogenous value, KMV's default point, and principal value of debt.Final, third chapter of the thesis, provides further evidence of the performance of the proposed pseudo maximum likelihood procedure and addresses the issue of the presence of non-default component in CDS spreads. Specifically, the effect of demand-supply imbalance, an important aspect of liquidity in the market where the number of buyers frequently outstrips the number of sellers, is analyzed. The data set is largely extended covering 163 non-financial companies (92 European and 71 North American) and period 2002-2008. In a nutshell, after controlling for the fundamentals reflected through theoretical, stock market implied credit spreads, demand-supply imbalance factors turn out to be important in explaining short-run CDS movements, especially during structural breaks. Results illustrate that CDS spreads reflect not only the price of credit protection, but also a premium for the anticipated cost of unwinding the position of protection sellers.

Made available in DSpace on 2015-03-03T15:28:33Z (GMT). No. of bitstreams: 1 RafaelaHSR_DISSERT.pdf: 2083489 bytes, checksum: 205ac27477b3c2a065fe9cb369c9200e (MD5) Previous issue date: 2013-02-28 / Coordena??o de Aperfei?oamento de Pessoal de N?vel Superior / In the work reported here we present theoretical and numerical results about a Risk Model with Interest Rate and Proportional Reinsurance based on the article Inequalities for the ruin probability in a controlled discrete-time risk process by Ros ario Romera and Maikol Diasparra (see [5]). Recursive and integral equations as well as upper bounds for the Ruin Probability are given considering three di erent approaches, namely, classical Lundberg inequality, Inductive approach and Martingale approach. Density estimation techniques (non-parametrics) are used to derive upper bounds for the Ruin Probability and the algorithms used in the simulation are presented / Neste trabalho apresentamos resultados te?ricos e num?ricos referentes a um Modelo de Risco com Taxa de Juros e Resseguro Proporcional baseados no artigo Inequalities for the ruin probability in a controlled discrete-time risk process de Ros?rio Romera e Maikol Diasparra (veja [5]). Equa??es recursivas e integrais para a Probabilidade de Ru?na s?o obtidas bem como cotas superiores para a mesma por diferentes abordagens, a saber, pela cl?ssica desigualdade de Lundberg, pela abordagem Indutiva e pela abordagem Martingale. T?cnicas de estima??o de densidade (n?o-param?tricas) s?o utilizadas para a obten??o das cotas para a Probabilidade de Ru?na e os algoritmos utilizados na simula??o s?o apresentados

No description available.

In this work we describe the basic facts of non-life insurance and then explain risk processes. In particular, we will explain in detail the asymptotic behavior of the probability that an insurance product may end up in ruin during its lifetime. As expected, the behavior of such asymptotic probability will be highly dependent on the tail distribution of each claim. / En este artículo describimos los conceptos básicos relacionados a seguros que no sean de vida y luego explicamos procesos de riesgo. En particular, tratamos al detalle el comportamiento asintótico de la probabilidad de que un producto sea declarado en ruina. Como es suponible, el comportamiento en el horizonte depende de la cola de la distribución de las primas.

Made available in DSpace on 2016-06-02T20:06:00Z (GMT). No. of bitstreams: 1 1662.pdf: 571364 bytes, checksum: 6091268473b4a7cb920748fd364c2a99 (MD5) Previous issue date: 2007-03-30 / Survival data analysis models is used to study experimental data where, normally, the variable "answer"is the time passed until an event of interest. Many authors do prefer modeling survival data, in the presence of co-variables, by using a hazard function - which is related with its interpretation. The Cox model (1972) - most commonly used by the authors - is applicable when the fail rates are proportional. This model is very flexible and used in the survival analysis. It can be easily extended to, for example, incorporate the time-dependent co-variables. In the present work we propose a proportional risk model which incorporates a time-dependent parameter named "time-dependent proportional risk model". / A análise de sobrevivência tem por objetivo estudar dados de experimento em que a variável resposta é o tempo até a ocorrência de um evento de interesse. Vários autores têm preferido modelar dados de sobrevivência na presença de covariáveis por meio da função de risco, fato este relacionado à sua interpretação. Ela descreve como a probabilidade instantânea de falha se modifca com o passar do tempo. Nesse contexto, um dos modelos mais utilizados é o modelo de Cox (Cox, 1972), onde a suposição básica para o seu uso é que as taxas de falhas sejam proporcionais. O modelo de riscos proporcionais de Cox é bastante flexível e extensivamente usado em análise de sobrevivência. Ele pode ser facilmente estendido para incorporar, por exemplo, o efeito de covariáveis dependentes do tempo. Neste estudo, propõe-se um modelo de risco proporcional, que incorpora um parâmetro dependente do tempo, denominado modelo de risco proporcional dependente do tempo. Uma análise clássica baseada nas propriedades assintóticas dos estimadores de máxima verossimilhança dos parâmetros envolvidos é desenvolvida, bem como um estudo de simulação via técnicas de reamostragem para estimação intervalar e testes de hipóteses dos parâmetros do modelo. É estudado o custo de estimar o efeito da covariável quando o parâmetro que mede o efeito do tempo é considerado na modelagem. E, finalizando, apresentamos uma abordagem do ponto de vista Bayesiano.

Orientador: Maria Alejandra Caporale Madi / Dissertação (mestrado) - Universidade Estadual de Campinas, Instituto de Economia / Made available in DSpace on 2018-08-04T01:32:34Z (GMT). No. of bitstreams: 1 Chianamea_DanteRicardo_M.pdf: 425425 bytes, checksum: 961e738189ae343b617ae6ea57b6235c (MD5) Previous issue date: 2004 / Resumo: : De acordo com a teoria econômica que se utiliza, os ciclos econômicos previstos assumem características diferentes: alguns supõem que exista uma regularidade, previsível por modelos estocásticos, em torno do custo de obtenção dos ativos reais; outros admitem desvios temporários, que podem ser previstos dentro de um prazo mais longo, entre o valor atribuído aos ativos e o valor real deles; e há um terceiro tipo que abrange as mudanças permanentes, que nem sempre podem ser previstas, de valor atribuído aos ativos. A eficácia da regulação prudencial, no sentido de manter o sistema financeiro saudável, depende do modelo de ciclo econômico considerado na sua elaboração, na medida em que estes afetam os valores dos ativos que compõem os balanços e os passivos contingentes das instituições financeiras. Este trabalho trata da evolução que o Acordo da Basiléia II e os novos modelos de risco a ele associados representam em relação ao primeiro Acordo, bem como das limitações que continuam pendentes / Abstract: Accordingly with economic theory employed, foreseeing economic cycles acquires proper characteristics: some suppose a pre-existing regularity, which is foreseeable by stochastic models on real business supply costs; other ones include temporary deviations from market to real values during the cycle time period but real values are detectable if we work in a longer time horizon; a third model has also considered permanent changes in market attributed values although they are not always predictable. The prudential regulation effectiveness - in the sense of reaching a soundness financial system ¿ depends on economic cycle model used in its development because of their influence in banks¿ balance asset values and contingent liabilities. This work is about Basel II Accord and new risk models evolution relative to the first Basel Accord and its models as well as their boundaries / Mestrado / Politica Economica / Mestre em Ciências Econômicas

The ability to predict stock returns is an ability many wish to possess, and in an accurate way as possible. For many years there has been an interest in the field of factor models explaining the returns, with the aim to increase the explanatory power. This is however a complex business since the factors and their improvement of explanatory power need to be significant. Now and then, researchers come up with new significant factors that have a positive impact on models. AQR Capital Management is no exception to this, since they in 2013 presented the factor Quality Minus Junk, earning significant risk-adjusted returns. This bachelor thesis work within mathematical statistics and industrial engineering and management, aims to investigate whether or not the commercial multi-factor model used at the public pension fund Fjärde AP-fonden will be improved by adding the factor Quality Minus Junk, in the sense of explanatory power. The method used is mainly based on multiple linear regression and three three-year time periods are studied ranging from 2010 to 2018. The results from this thesis work show that the QMJ factor provides significant increases in explanatory power for one of three time periods, the most recent period 2016$-$2018. However, since the results are inconclusive further studies are needed in order to better understand how to interpret the results and whether or not to include the QMJ factor in the model. / Förmågan att förutsäga aktiers avkastning önskar många besitta, och på ett så precist sätt som möjligt. Under många år har forskning pågått inom området för faktormodeller som förklarar avkastningar, med målet att öka modellernas förklaringsgrad. Detta är dock en komplex verksamhet eftersom faktorerna och deras förbättring av förklaringsgraden måste vara signifikanta för modellen. Då och då kommer forskare fram med nya sådana faktorer som har positiv påverkan på modeller. AQR Capital Management är inget undantag eftersom de 2013 presenterade sin faktor Quality Minus Junk som visar signifikanta riskjusterade avkastningar. Detta kandidatexamensarbete inom matematisk statistik och industriell ekonomi, ämnar att utreda huruvida den kommersiella faktormodellen som används på Fjärde AP-fonden förbättras genom tillägget av faktorn Quality Minus Junk, i förklaringsgradsmening. Metoden som används är till största delen baserad på multipel linjär regression och tre treårsperioder studeras i tidsintervallet 2010 till 2018. Resultaten från detta projekt visar på att faktorn Quality Minus Junk bidrar med signifikanta ökningar av förklaringsgraden för en av tre perioder, den senaste perioden 2016-2018. Eftersom resultaten är inkonklusiva krävs vidare studier för att bättre förstå och konkludera vad dessa resultat faktiskt innebär samt för att inkludera QMJ-faktorn i modellen eller ej.

No description available.

Thesis (MA (Political Science))--University of Stellenbosch, 2010. / ENGLISH ABSTRACT: Political risk analysis is considered one of the essential ingredients in decision making processes when investing abroad. The Iranian Revolution and the oil crisis in the 1970s accentuated this need as investors increasingly felt the need for a proper assessment of the risks involved in establishing a business in other countries. Negative images of African countries combined with conventional risk models which are not able to accurately assess the political risk realities of post-conflict African countries, may be one of the reasons for why African countries struggle to attract a substantial amount of FDI. This study suggests that alternative risk models which are more African-orientated may aid in improving this situation. This study has analysed the political risk of Sierra Leone using a conventional risk model, and an African-orientated political risk model. The aim of this study was to assess whether conventional political risk models need to be adjusted to be able to more accurately assess the political risk of post-conflict African countries. The main research question guiding this study was:  Are conventional risk models able to objectively rate the political risk of post-conflict countries in Africa? The conclusion of this research was that African-orientated political risk models are able to more accurately assess the political risk of a post-conflict African country such as Sierra Leone. This is mainly due to the soft variables used in a political risk model and also the relationship between the variables included in the models. The African-orientated political risk model needs to be analysed further, but this research has made clear the need for a reevaluation of existing political risk models to be better equipped when analysing post-conflict African countries. This will not only benefit African post-conflict countries in improving their risk ratings, but also provide foreign investors with a more accurate identification of the potential political risks facing an investment in post-conflict African countries. It was acknowledged in this study that the political risk analyses of Sierra Leone were not conducted by someone who has inside information of the political risk models used which is a limitation iii for the results of this study. It is, however, possible to detect potential weaknesses with each political risk model and possible areas of improvements. / AFRIKAANSE OPSOMMING: Politieke Risiko Analise word as een van die belangrikste bestandele in die besluitnemingsproses geag wanneer daar oorsee belê word. Die Iranese Rewolusie en die Olie krisis in die 1970’s het hierdie nood beklemtoon, aangesien beleggers toenemend die belang van deurdagte assesering van die risikos in verband met die oprigting en instandhouding van besighede in ander lande erken het. Negatiewe opvattings van Afrika lande, tesame met konventionele risiko modelle wat nie geskik is on akkurate asseserings van politike risiko realiteite op te lewer, is dalk van die redes waarom Afrika lande sukkel om groot Direkte Buitelandse Beleggings te lok. Hierdie studie stel voor dat alternatiewe risiko modelle wat meer Afrika-gesind van aard is die situasie kan help oorbrug. Hierdie studie het die politieke risiko situasie van die Sierra Leone analiseer aangaande‘n konvensionele riskio model en met behulp van’n Afrika-georienteerde politieke risiko model. Die studie het gepoog om te assesseer of die konvensionele modelle van politieke risiko gewysig moet word om in staat te wees om meer akkuraat te oordeel in verband met politieke risiko in post-konflik Afrika lande. Die hoof navorsingsvraag wat die studie gedryf het is die volgende: Is die konvensionele risiko modelle in staat om objektief te werk te gaan om die politieke risiko van post-konflik lande in Afrika te meet? Die gevolgtrekking van hierdie navorsing is dat die Afrika-georienteerde politieke risiko modelle meer gepas is om die politike risiko van post-konflik lande soos Sierra Leone te meet. Dit is hoofsaaklik die geval weens die sagte veranderlikes wat gebruik word in’n politieke risiko model asook die verband tussen die veranderlikes wat in die model ingesluit word. Die Afrika-georienteerde politieke risiko model moet verder uitgebrei word, alhoewel hierdie navorsing dit duidelik maak dat die belang bestaan vir‘n herevaluering van die bestaande politieke risiko modelle om beter toegerus te wees om analise van post-konflik Afrika lande uit te voer. Dit word erken dat hierdie studie van die politieke risiko van Sierra Leone nie uitgevoer was deur iemand wat‘n intieme kennis van politieke risiko modelle het nie. Dit is uiteindelik wel moontlik on potensiele swak plekke in die mondering van elke politieke risiko model uit te sonder, en moontlike areas van verbetering voor te stel.