The six lessons for Class 4 are now available on the course website:
In this class we'll learn about two topics: attribute selection and cost-sensitive classification. Automatic selection of an attribute subset is a powerful way of getting both good results and simpler, easily explainable, models from machine learning; indeed you will end up achieving stunning results with a tiny subset of attributes on a document classification task. And taking the costs of different kinds of error into account is essential in many practical applications.
Next week is the last. Pretty soon you will be an expert in data mining and the use of Weka!
It's great to see so many people helping each other on the course forum. Please keep it up -- we greatly value your assistance.