Measure Theory and Stochastic Processes II
2014-2015
Duisenberg School of Finance

Aim

To make students familiar with the mathematical fundamentals of stochastic processes and stochastic integrals. After the course students should be able to apply the theory to certain problems arising in derivative pricing and credit risk.

Contents

Construction of Brownian motion from symmetric walk by the central limit theorem, martingale property and quadratic variation; construction of the Itô integral, fundamental properties (Itô isometry); Itô rule (in one and more dimensions), stochastic product rule, Lévy's characterization of Brownian motion; absolutely continuous change of measure, Girsanov's theorem, martingale representation theorem; stochastic differential equations, Poisson and compound Poisson process, decomposition of compound Poisson processes, quadratic variation, Itô formula for processes with jumps.

Prerequisites

Basic concepts of probability and measure theory, as given in the course by Laurens de Haan.

Literature

The course is mainly based on Steve Shreve, Stochastic Calculus for Finance II, Continuous-Time Models, Springer (2004).

Examination

Weekly a set of homework assignments and a final written exam at the end. You are required to work in pairs (and a pair means two people only!) for the homework. Deadlines are always a week after the assignment has been made known. The written exam will be on January 8, 2015. You can prepare for the exam by looking at old exam questions. Be aware of the fact that some of these refer to topics in Shreve that have not been present in this year's course. So you simply ignore questions where you encounter unfamiliar things.

People

Lectures by Peter Spreij, tutorials by Andrei Lalu.

Schedule

Location

Duisenberg school of finance, Gustav Mahlerlaan 117, 1082 MS Amsterdam (travel directions).

Programme

1
Class: Random walk, Central limit theorem, Brownian motion, martingale, quadratic variation; from Shreve, most (but not all!) of Sections 3.1-3.4.1.
TA session: Exercises 3.5, 3.6; as a preparation you have a look at Section 3.5.
Homework: Exercises 3.1, 3.2.
2
Class: Quadratic variation of Brownian motion, stochastic integral of simple functions; from Shreve, most of Section 4.2.
TA session: Exercises 3,4, 4.2.
Homework: Exercises 4.1, 4.3.
3
Class: Itô integral continued, $\int_0^TW(t)\,\mathrm{d}W(t)$, Itô-formula for Brownian motion and Itô processes, from Shreve, Sections 4.3. 4.4.
TA session: Exercises 4,4, 4.5.
Homework: Exercises 4.6, 4.7.
4
Class: Itô integrals with deterministic integrands; multivariate Brownian motion, product rule, Levy's characterization; from Shreve, remainder of Section 4.4, Sections 4.6.1, most of Sections 4.6.2 and 4.6.3.
TA session: Exercises 4.10 (lengthy story, but there is not much work), 4.13, 4.18.
Homework: Understand the examples in Section 4.4, pay attention to the parts of Section 4.6 that I skipped, and make Exercises 4.8, 4.14, 4.15.
5
Class: Levy's characterization, change of measure, Girsanov's theorem; risk neutral pricing in finance; from Shreve, Sections 5.2.1-5.2.4, perhaps 5.3.
TA session: Exercises 4.9 (recall Exercise 3.5), 5.3.
Homework: Read Section 5.2.5, make Exercises 5.1, 5.2.
6
Class: martingale representation theorem, start with Poisson processes; from Shreve, Sections 5.3, 11.2.
TA session: Exercises 5.5. 5.12 (for which you have to pick up the essentials of Sections 5.4.1 and 5.4.2, they are multivariate versions of what you already know).
Homework: Exercises 5.8, 5.11.
7
Class: Compound Poisson process, integrals w.r.t. jump processes; from Shreve, Section 11.3, 11.4 and some highlights from Section 11.5.
TA session: Exercises 11.3, 11.4; Exercise 8.3(b) from the lecture notes of another course in which you have to find the process $\Gamma$ of Theorem 5.3.1 for the martingales in the exercise (do this for $t \leq T$ only). Don't get confused by the notation $X\cdot W$. It means the stochastic integral $\int X(s)\,\mathrm{d}W(s)$, not a product (this notation is not uncommon, by the way, see also Williams for a discrete time version).
Homework: Exercise 8.3(b) from the lecture notes as above. Further: Exercises 11.1 (first (ii), than (i)), 11.2.




Links

Korteweg-de Vries Institute for Mathematics
Master Stochastics and Financial Mathematics