MATH 606, Summer 2020.
Topics in Stochastic Processes (054–39482R)
Understanding the Bichteler-Dellacherie Theorem
Class meetings: MW, 9:30am-12:30pm, On line.

 

Information on this and related pages changes frequently.

Instructor: Sergey Lototsky.
Office: KAP 248D.
Phone: 213 740 2389
E-mail: lototsky usc edu.

URL: https://dornsife.usc.edu/sergey-lototsky/

Office Hours: MW 12:30-1:30pm, on line [May 20-July 6]
Appointments at other time are welcome.

Course objective To understand why a consistent stochastic integration is only possible with respect to semi-martingales

Course work: Class participation, homework assignments, final presentation.

Official grading scheme: 20% class participation, 40% homework assignments, 40% final presentation.

Main reference: Stochastic Integration and Differential Equations, by Philip Protter; Any Edition, Springer, from 1990 on, 300 pp.

Other references

  1. Karatzas and Shreve, Browinian Motion and Stochastic Calculus, Springer, from 1988 on, 500 pp.
  2. Liptser and Shiryaev, Theory of Martingales, Kluwer/Springer, from 1986 on, 800 pp.
  3. An alternative proof of the theorem [pre-print; published as Beiglböck, M. and Siorpaes, P. Riemann-integration and a new proof of the Bichteler-Dellacherie theorem. Stochastic Process. Appl. 124 (2014), no. 3, pages 1226–1235.]

Closely related fun reads

  1. Burk, A Garden of Integrals, MAA, 2007.
  2. Gelbaum and Olmsted, Counterexamples in Analysis, from 1964 on [e.g. Dover, 2003].
  3. Stoyanov, Counterexamples in Probability, Wiley, from 1987 on.
  4. Szekely, Paradoxes in Probability Theory and Mathematical Statistics, Kluwer, from 1986 on.

Highlights of the course, including homework problems, will be updated on a regular basis and appear at the top of the content section of Blackboard

Lecture notes: at least two versions will be uploaded to the content section of Blackboard after every lecture.

The plan
Introduction and outline; Deterministic integration; Summary of Functional Analysis; Review of Basic Probability; Stochastic Analysis I: sigma-algebras and stopping times; Stochastic Analysis II: different types of processes; Stochastic Analysis III: martingales and related concepts; Properties of the Stochastic Integral, Cameron-Martin-Girsanov-Meyer; The Proof; Some examples and counterexamples.

Our Progress

May 20. Understanding the task: stochastic integration as a bounded linear operator.

May 25. Memorial Day: no class.
May 27. An overview of integration: from Cauchy and Riemann to Henstock-Kuzweil and Ito.

June 1. Deterministic integration: importance of bounded variation.
June 3. Functional analysis and probability: topology vs sigma-algebra.

June 8. Functional analysis: the main theorems.
June 10. Stochastic analysis: the foundations.

June 15. Martingales and the idea of the proof.
June 17. Quasimartingales and the proof.

June 22. What is behind: Theorems of Cameron-Martin-Girsanov-Meyer, Doob-Meyer, and Rao.
June 24. Semimartingales and stochastic integrals: general properties

June 9. Martingales: inequalities, convergence, and change of measure.
July 1. A summary: examples and counterexamples.

July 6. A problem-solving session.