The information metrics at its heart were presented in class and are in your notes. Below I provide you with the algorithm in an easily implementable form and describe the data sets you should use for development and testing. The ID3 algorithm recursively constructs subtrees by selecting the attribute with the highest gain for each root. The information gain equation was provided in class and should be used with this algorithm.
Test is the data set described in class for classifying sunburns.
It should be useful for debugging as your notes include the information gain calculations for the first decision node. The other two are taken from the Machine Learning data repository at UC Irvine. Car describes features for selecting a car to buy. The data set includes six features and 1728 cases. Nursery describes applicants to nursery school in Slovenia.