what is the difference between "use training set" and "supplied test set" in weka.How does it help in calculating regression?

Question

Hey I am asked to prepare two .arff files and to apply training set for regression calculation on one file and to apply test set for the other... Kindly help me what is the difference between training set and supplied test set in weka.

Answer 1

Use training set: The classifier is evaluated on how well it predicts the class of the instances it was trained on.

Supplied test set: The classifier is evaluated on how well it predicts the class of a set of instances loaded from a file.