Probabilistic & Unsupervised Learning (2008)

Dates Mondays & Thursdays
29 September - 4 December 2008
Time 11:00-13:00
Tutorials Wednesdays 14:00-15:30
Lecturers Yee Whye Teh and Maneesh Sahani
TA Vinayak Rao
Location 4th Floor Seminar Room, Alexandra House, 17 Queen Square, London [directions]
About the course

This course provides students with an in-depth introduction to statistical modelling, unsupervised, and some supervised learning techniques. It presents probabilistic approaches to modelling and their relation to coding theory and Bayesian statistics. A variety of latent variable models will be covered including mixture models (used for clustering), dimensionality reduction methods, time series models such as hidden Markov models which are used in speech recognition and bioinformatics, Gaussian process models, independent components analysis, hierarchical models, and nonlinear models. The course will present the foundations of probabilistic graphical models (e.g. Bayesian networks and Markov networks) as an overarching framework for unsupervised modelling. We will cover Markov chain Monte Carlo sampling methods and variational approximations for inference. Time permitting, students will also learn about other topics in probabilistic (or Bayesian) machine learning.

The course is run primarily for new Gatsby students for whom it is mandatory. It is also an optional course for students on the UCL MSc in Machine Learning and UCL MSc in Computational Statistics and Machine Learning. Students, postdocs and faculty from outside the unit and these programmes are welcome to attend, but should contact the unit in advance.


A good background in statistics, calculus, linear algebra, and computer science. You should thoroughly review the maths in the following cribsheet [pdf] [ps] before the start of the course. You must either know Matlab or Octave, be taking a class on Matlab/Octave, or be willing to learn it on your own. Any student or researcher at UCL meeting these requirements is welcome to attend the lectures.


There is no required textbook. However, the following are excellent sources for many of the topics covered here.

David J.C. MacKay (2003) Information Theory, Inference, and Learning Algorithms, Cambridge University Press. (also available online)
Christopher M. Bishop (2006) Pattern Recognition and Machine Learning, Springer-Verlag.
Specific recommendations for reading are available as the course progresses. Lecture slides and assignments will be posted here in due course.
Lecture schedule
29/09: Introduction 2/10: Statistical Foundations
6/10: Latent Variable Models 9/10: continued
13/10: The EM algorithm [demo] 16/10: continued
20/10: Time Series models 23/10: continued
27/10: Graphical Models 30/10: continued
3/11: Hierarchical and Nonlinear Models 6/11: continued
10/11: Bayesian Treatments of Probabilistic Models 13/11: Variational approximations
17/11: Sampling and Monte Carlo 20/11: continued
24/11: Expectation Propagation 27/11: Belief Propagation
1/12: Convex Approximations 4/12: Final wrapup
50% of the total mark is based on coursework assignments (the other 50% being based on the final written examination).

All assignments (coursework) are to be handed in to the Gatsby Unit, not to the CS department. Please hand in all assignments at the beginning of lecture on the due date to the lecturer or to Deb. Late assignments will be penalised. If you are unable to attend the lecture, you can also hand in assignments to Ms. Rachel Howes at the Alexandra House 4th floor reception.

Late Assignment Policy: Assignments that are handed in late will be penalised as follows: 10% penalty per day for every weekday late, until the answers are discussed in a review session. NO CREDIT will be given for assignments that are handed in after answers are discussed in the review session.

Assignment 0 due 6 Oct 2008
Assignment 1        [binarydigits.txt, bindigit.m] due 20 Oct 2008
Assignment 2        [geyser.txt, data3d.txt] due 3 Nov 2008
Assignment 3        [co2.txt] due 20 Nov 2008
Assignment 4        [message.txt, symbols.txt, code.tgz] due 4 Dec 2008
Assignment 5        [images.jpg, genimages.m, Mstep.m] due 18 Dec 2008

To attend Please contact the unit.