Context-Specific CPDs

1. Representation Probabilistic Graphical Models Local Structure Context-Specific CPDs

2. Tree CPD A a0 a1 S (0.8,0.2) s0 s1 Apply L (0.1,0.9) l0 l1 Letter SAT (0.9,0.1) (0.4,0.6) Job

3. Which context-specific independencies are implied by the structure of this CPD? (Mark all that apply.) A a0 a1 S (0.8,0.2) s0 s1 L (0.1,0.9) l0 l1 (0.9,0.1) (0.4,0.6)

4. Tree CPD C c1 c2 L2 L1 l0 l0 l1 l1 Choice (0.8,0.2) (0.9,0.1) (0.1,0.9) (0.3,0.7) Letter1 Letter2 Job

5. Which non-context-specific independency is implied by the structure of this CPD? C c1 c2 L L l0 l0 l1 l1 (0.9,0.1) (0.8,0.2) (0.1,0.9) (0.3,0.7) Choice Letter1 Letter2 Job

6. C c1 c2 L L l0 l0 l1 l1 (0.8,0.2) (0.9,0.1) (0.1,0.9) (0.3,0.7) Choice Letter1 Letter2 Job

7. Multiplexer CPD . . . Z1 Z2 Zk A Y

8. Microsoft Troubleshooters # of parameters: 145 to 55

9. END END END

10. Suppose q is at a local minimum of a function. What will one iteration of gradient descent do? Leave q unchanged. Change q in a random direction. Move q towards the global minimum of J(q). Decrease q.

11. Consider the weight update: Which of these is a correct vectorized implementation?

12. Fig. A corresponds to a=0.01, Fig. B to a=0.1, Fig. C to a=1. Fig. A corresponds to a=0.1, Fig. B to a=0.01, Fig. C to a=1. Fig. A corresponds to a=1, Fig. B to a=0.01, Fig. C to a=0.1. Fig. A corresponds to a=1, Fig. B to a=0.1, Fig. C to a=0.01.