Bayesian Classifiers

Autonomous Agents, Fall semester 2019

Vasilis Papageorgiou: Github account, Linkedin account

Downloads: source code, report, presentation

Description

In this project, we study the case of Bayesian Network statistical classifiers, which utilize the properties of traditional Bayesian Networks aiming to classify random variable observations to a specific class, by implementing algorithms of structure learning and parameter estimation. More specifically, we implement two well known Bayes based classifiers, the Naive Bayes and the Tree Augmented Naive Bayes classifier. Both classifiers make some independence assumptions between the attributes, which in both cases are treated as random variables.

The algorithms above where tested in the networks that are shown below. The first on is the widely used alarm network and the second one a medical network that can be used to classify patients. We firstly created two artificial datasets using prior sampling on both the networks and then - based on these data- we learnt the parameters and the structure of two new networks, whose performance was then examined.

Results

Below, we can see how both the classifiers operate compared to the inital Bayesian networks for the classification task in the case of various labels