Tutorial by Examples

The Iris flower data set is a widely used data set for demonstration purposes. We will load it, inspect it and slightly modify it for later use. import java.io.File; import java.net.URL; import weka.core.Instances; import weka.core.converters.ArffSaver; import weka.core.converters.CSVLoader; i...

ZeroR is a simple classifier. It doesn't operate per instance instead it operates on general distribution of the classes. It selects the class with the largest a priori probability. It is not a good classifier in the sense that it doesn't use any information in the candidate, but it is often used as...

In order to build a good classifier we will often need to get an idea of how the data is structered in feature space. Weka offers a visualisation module that can help. Some dimensions already seperate the classes quite well. Petal-width orders the concept quite neatly, when compared to petal-widt...

Trees can build models that work on independent features and on second order effects. So they might be good candidates for this domain. Trees are rules that are chaind together, a rule splits instances that arrive at a rule in subgroups, that pass to the rules under the rule. Tree Learners generate...