11468-FS2024-0-Stochastic Processes II





Root number 11468
Semester FS2024
Type of course Lecture
Allocation to subject Statistics
Type of exam Oral exam
Title Stochastic Processes II
Description Random elements in functional spaces (cylindrical sigma-algebra, finite dimensional distributions of a stochastic process; Kolmogorov's theorem on finite dimensional distributions (with proof); mean and variance function of a stochastic process; stationarity properties of stochastic processes; Gaussian processes and their finite dimensional distributions, finite dimensional distribution of the Wiener process; equivalent processes and modifications (versions), stochastic continuity; separability (existence of a separable version - formulation without proof); continuity of sample paths, Kolmogorov's continuity criterion (proof), its application to the Wiener process (proof); definitions of continuous time filtration, stopping times and progressive measurability, progressive measurability of right-continuous processes, definition of continuous time martingales.)
Markov processes (transition kernels and the Chapman--Kolmogorov equation; operators acting on functions and measures, strong Markov property; 0-1 law of Blumenthal (proof); definition of the generating operator.)
Brownian motion (the Wiener process) (definition and its equivalent variants (with proofs of equivalence); covariance function and calculation of distributions, in particular integrals of the Wiener process; key properties (scale invariance, time shift, symmetry, time inversion) with proofs; Markov and strong Markov properties (proof); Brownian bridge and its basic properties; Brownian motion in higher dimensions; quadratic and linear variation of the Wiener process (proofs), non-differentiability (without proof); reflection principle (proof); derivation of the distribution of supremum of the Wiener process, and of the first hitting time; level sets, zero set and the arcsine law (proof); martingale properties of the Brownian motion, Wald's identities (without proofs).
Stochastic integration (problems with the classical definition of the integral with respect to the Wiener process; It^o's stochastic integral for step functions, proof of It^o's isometry for step functions; extension for progressively measurable functions, It\^o's isometry, It\^o integrable functions (on the half-line); martingale properties of the stochastic integral, existence of a continuous modification (with proofs), Wald's identities (without proof); It\^o processes, It\^o's formula (proof only for $df(W_t)$), its variants and applications to calculation of stochastic integrals, product rule for stochastic differentials; multidimensional It\^o's formula (proof using calculus rule for stochastic differentials); basic ideas of stochastic differential equations; basic examples (geometric Brownian motion, Ornstein-Uhlenbeck).)
L'evy processes (definition of infinitely divisible random variables with examples; L'evy-Khintchine formula (be able to show the integrability in the jump part), condition on the L'evy measure; definition of L'evy processes and examples; Poisson and compound Poisson processes; idea of a construction of the L'evy process from three parts (Gaussian, compound Poisson and small jumps), relation to the Poisson process; L'evy processes with finite linear variation (idea of the proof); operators P_t associated with the L'evy process and the resolvent U^q (definitions and formulations of basic properties); definition of the potential measure and recurrence/transience properties of the L'evy process, be able to apply the Chung-Fuchs criterium (proof for dimension one); s
ILIAS-Link (Learning resource for course) Registrations are transmitted from CTS to ILIAS (no admission in ILIAS possible). ILIAS
Link to another web site
Lecturers Prof. Dr. Ilya MolchanovInstitute of Mathematical Statistics and Actuarial Science 
PD Dr. Andrii IlienkoInstitute of Mathematical Statistics and Actuarial Science 
ECTS 6
Recognition as optional course possible No
Grading 1 to 6
 
Dates Monday 08:15-10:00 Weekly
Wednesday 08:15-10:00 Weekly
Tuesday 25/6/2024 09:00-13:00
 
Rooms Hörraum B078, Exakte Wissenschaften, ExWi
 
Students please consult the detailed view for complete information on dates, rooms and planned podcasts.