Uncertainty:Bayesian networks Flashcards
(15 cards)
Conditional Independence
Two variables are conditionally independent if they are independent given the knowledge of a third variable.
Bayesian Network
A graphical model representing probabilistic relationships among variables using nodes and directed edges.
Directed Acyclic Graph (DAG)
A graph with directed edges and no cycles
Conditional Probability Table (CPT)
A table that defines the probability of a node given the values of its parent nodes in a Bayesian network.
Causality
One variable’s direct effect on another variable.
Correlation
The statistical degree to which two variables change together.
Hidden Variables
Variables that are not observed but affect the system in question.
Evidences
Known values of observed data used in inference.
Joint Distribution
The probability of all possible combinations of values for all variables in a system.
Exact Inference
Computing the exact posterior probabilities or distributions over variables given evidence.
Enumeration
An exact inference technique that sums over all values of hidden variables.
Caching
Storing the results of expensive computations to avoid repeating them.
Approximate Inference
A technique of estimating the probability values or distributions of variables.
Direct Sampling
An approximate inference method that estimates probabilities based on the frequency of sampled outcomes.
Joint Probability Distribution Factorization
Making the joint probability of the network simpler by expressing it as a product of conditional probabilities.