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Representation. Probabilistic Graphical Models. Wrapup. Knowledge Engineering. Important Distinctions. Template based versus specific Directed versus undirected Generative versus discriminative Hybrids are also common. Important Distinctions. Template-based. Specific.
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Representation Probabilistic Graphical Models Wrapup Knowledge Engineering
Important Distinctions • Template based versus specific • Directed versus undirected • Generative versus discriminative • Hybrids are also common
Important Distinctions Template-based Specific
Important Distinctions Generative Discriminative
Variable Types • Target • Observed • Including complex, constructed features • Latent GMT … W1 W2 W3 Wk
Structure • Causal versus non-causal ordering GMT … … W1 W1 W2 W2 W3 W3 Wk Wk GMT
Parameters: Values • What matters: • Zeros • Orders of magnitude • Relative values • Structured CPDs
Parameters: Local Structure • Table CPDs are the exception
Iterative Refinement • Model testing • Sensitivity analysis for parameters • Error analysis • Add features • Add dependencies