This document describes one of the available topics for the MSc-project in Financial Mathematics.
This document describes one of the available topics for the MSc-project in Financial Mathematics. The focus is on an investor who holds a portfolio of assets and who wants to compute and interpret certain risk measures in order to guide future actions in an environment with negative rates.
first part is a literature review that would de- scribe and explain the contracts in the portfolio, the models used for equity/ interest rates, the methods available for the modelling of the default, the meth- ods used to estimate the parameters, and the most common risk measures. The second part consists of a numerical analysis of a specified portfolio, where the models would be implemented on a practical level. The third part treats more advanced issues related to this topic, with a view of enhancing the understanding of the problem, the model and the results.
Implementing such a project in real life would require at a minimum identi- fying the risk factors and appropriate models for them, checking if counterparty credit risk is present, and how to model it if necessary, identifying which real market data to be used for parameter estimation and how long the historical time series should be.
To facilitate the analysis we provide guidance for some of the steps mentioned above. The risk factors are modelled with stochastic models that have been introduced in previous modules, and the parameters of the models are estimated using real data from Bloomberg over the specified time horizon. Future paths are generated according to these models, and the possible future values are incorporated in a risk analysis through the computation of risk measures for the portfolio.
where the counterparty of a certain contract in the portfolio can default before the maturity of the contract, thereby affecting the payoff of the contract. For our portfolio we consider a reduced-form model with constant intensity of default that will model the occurrence of the default. The parameters for this model of default can be calibrated to market data (e.g. CDS market prices), but we will assume specific values for them.
In the first part the student is asked to write a literature review that should include a description of the contracts in the portfolio, particularly the EONIA- based interest rate swap, a brief outline of the models used for equity/ interest rates, the methods available for the modelling of the default (i.e. structural vs reduced form models, advantages and disadvantages of each class), a brief outline of the methods used to estimate the parameters, and a review of the most common risk measures.
The student is invited to consult a number of publications on EONIA/ECB rates, Credit Risk modeling, and on Value at Risk and risk measures in general.
The references at the end of this document are classical books on risk man- agement, interest rate models, least squares parameter estimation and related topics, and give good starting points to the literature. The student should be proactive in researching the literature, which involves published journal papers and books. Working papers should be used mostly for orientation, given that their content has not been peer reviewed.
It is particularly important that the student synthesizes the information gathered from these sources and presents it as a flowing story that is consistent both in terms of notation and mathematical and financial content.
This part applies the theoretical notions from Part 1 on an analysis of a specific portfolio. The assets in the portfolio are:
The goal of the project is to analyse the risk and return characteristics of the portfolio using a stochastic model for the underlying risk factors.
Consider the risk factors to be the equity (DAX) and the EONIA spread over the ECB deposit rate:
Xt = (log Yt log St)j,
and assume they follow under the subjective measure P a discretized version of a stochastic differential equation (SDE) of the type:
∆Xt = (AXt−∆t + b)∆t + ε, ε ∼ N (0, Σ),
where ∆t = 1 day (for tractability make the simplifying assumption that week- ends or holidays are equivalent to 1 day periods).
Analyse the distribution of the potential losses incurred by the portfolio over a 30 days holding period, and use VaR and ES (CVaR) to quantify them with confidence level 99%. The relative losses are defined wrt to the value V1 of the portfolio in 30 days from t = 0 and the value V0 at time t = 0 (you can consider the percentage change in the value of the portfolio for instance). Analyse the numerical accuracy of the results.
To compute the value V0 find the equity price, the option price and the swap rate on the date t = 0 in the Bloomberg terminal, and explain how you obtained them.
For V1 simulate 30 days for the process Y , and simulate also the default of the counterparty of the call. Plot one future sample path together with the historical path for each component of the process X.
Include in your analysis the histogram of the relative losses, a plot of the return distribution of the portfolio, computation of VaR and ES, and the expected and median returns of the portfolio.
Analyse the impact of credit risk by repeating the calculations without credit risk (zero intensity) and comparing the results. Discuss.
Summarize your answers by completing a table in the format shown in Table 1.
Portfolio |
Expected
returns |
Median
returns |
V@R | CV@R |
credit risk | ||||
no credit risk |
Table 1: Format to use for the display of the results
All students on the MSc course in Financial Mathematics are required to submit the dissertation. The following describes what this involves.
The MSc dissertation consists of a review of a suggested area of currently active research in mathematical finance, with the addition of some specific ap- plication and with possible developments. It would be good if a student could produce some original research in the final part of the dissertation,
What the faculty is hoping to see is a critical understanding of the literature, including acquired results, open problems, current difficulties, past importance and potential for future applica- tions, and the ability to apply what has been understood in a practical case. When reading the dissertation, the examiners will try to see whether the stu- dent has absorbed and understood the material while presenting it in her own way, and whether the student has been able to implement the ideas effectively.
Important: The student should not copy whole sentences or even paragraphs directly from published papers, and should write her own code. Violations are easily noticed by markers and would be penal- ized. Furthermore, all sources must be properly referenced.
The dissertation must be an independent piece of work. While it can be helpful to talk with other students who are writing the disserta- tion, the ftnal work produced by the student should not be collabo- rative.
Before resorting to advisors for help the students are encouraged to be proac- tive in solving their problems. It it expected that students resort to advisor help for substantial matters and only as a last resort. Advisors should not be con- tacted for trivial suggestions.