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Bayesian Classification:
• Bayesian classifiers are statistical classifiers.
• They can predict class membership probabilities, such as the probability that a given tuple belongs to a particular class.
• Each Bayesian example can incrementally increase or decrease the probability that a hypothesis is correct-prior knowledge can be combined with observed data.
• Bayesian classification is based on Bayesian theorem.
• Bayesian classifiers have also exhibited high accuracy and speed when applied to large databases.
Naïve Bayesian classifiers:
• These assume that the effect of an attribute value on a given class is independent of the values of the other attributes.
• This assumption is called class conditional independence.
• It is made to simplify the computations involved in this.
Bayesian Theorem:
• The purpose of Bayesian theorem is to predict the class label for a given tuple.
• Let X be a data tuple.
• In Bayesian terms, X is considered “evidence.”
• it is described by measurements made on a set of n attributes.
• Let H be some hypothesis, such as that the data tuple X belongs to a specified class C.
• For classification problems, we are looking for the probability that tuple X belongs to class C, given that we know the attribute description of X.