Contents of Joe Chang's Stochastic Processes notes
- Chapter 1: Markov chains
- What is a Markov chain? How to simulate one.
- The Markov property.
- How matrix multiplication gets into the picture.
- Statement of the Basic Limit Theorem about convergence to stationarity. A motivating example shows how complicated random objects can be generated using Markov chains.
- Stationary distributions, with examples. Probability flux.
- Other concepts from the Basic Limit Theorem: irreducibility, periodicity, and recurrence.
An interesting classical example: recurrence or transience of random walks.
- Introduces the idea of coupling.
- Uses coupling to prove the Basic Limit Theorem.
- A Strong Law of Large Numbers for Markov chains.
- Chapter 2: More on Markov chains, Examples and Applications
- Branching processes.
- Time reversibility.
- Application of time reversibility: a tandem queue model.
- The Metropolis method.
- Simulated annealing.
- Ergodicity concepts for time-inhomogeneous Markov chains.
- Proof of the main theorem of simulated annealing.
- Card shuffling: speed of convergence to stationarity.
- Chapter 3: Markov Random Fields and Hidden Markov Models
- MRF's on graphs and HMM's.
- Bayesian framework
- The Hammersley-Clifford Theorem and Gibbs Distributions
- Phase transitions in the Ising model.
- Likelihood and data analysis in hidden Markov chains.
- Simulated MRF's, the Gibbs' sampler.
- Chapter 4: Martingales
- Where did the name come from?
- Definition and examples.
- Optional sampling.
- Stochastic integrals and option pricing in discrete time.
- Martingale convergence.
- Stochastic approximation.
- Chapter 5: Brownian motion
- The definition and some simple properties.
- Visualizing Brownian motion. Discussion and demystification of some strange and scary pathologies.
- The reflection principle.
- Conditional distribution of Brownian motion at some point in time, given observed values at some other times.
- Existence of Brownian motion. How to construct Brownian motion from familiar objects.
- Brownian bridge. Application to testing for unformity.
- A boundary crossing problem solved in two ways: differential equations and martingales.
- Discussion of some issues about probability spaces and modeling.
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Chapter 6: Diffusions and Stochastic Calculus