1. 10/19

2. Survey Summary 18 filled the survey – Will make the full results available by email Most seem happy with the lectures Most say they spend 2- 6 hours per week reading Presentations: all but one either prefers are doesn’t mind having student presentations on Fridays Midterm: Most people who had an opinion thought it would be good to have.

3. Lay of the land Uncertainty vs. Utility Uncertainty Uncertainty can be handled in terms of a quantitative probability theory (assuming certain axioms, including the disjunction axiom) – If you want a probability theory without those axioms, then de Finetti will take all your money Elementary probability theory based on joint probabilities has two problems: it needs too many numbers, and it requires hard to assess numbers – To make assessment more natural, focus on conditional probabilities (and pray to Rev Bayes) – To reduce the number of numbers, state and exploit conditional independence assumptions Under independence, joint probabilities can be computed as a products of individual probabilities Often there are too many conditional independence assumptions (some of which follow from others) and it is hard to list them all, and exploit them systematically – Use graphical models, such as bayes networks Preferences Preferences can be handles in terms of a quantitative utility theory (assuming certain axioms, including transitivity, continuity, monotonicity of preferences) – If you want a preference theory without these axioms, I can design lotteries where I can steal all your money Elementary utility theory is based on utilities over states (if states are defined in a factored model, these can be seen as joint utilities). This has two problems. It needs too many numbers, and it requires hard to assess numbers – To make assessment natural, focus on attribute and conditional attribute utilities – To reduce the number of numbers, state and exploit utility independence assumptions Under independence, joint utilities can be computed as sums of individual utilities Often there are too many independence assumptions (some of which follow from others) and it is hard to state and exploit them all systematically – Use graphical models, such as CP-nets and UCP-nets

23. Compilation and learning are very related