How to Handle Missing Data? a Ignore the tuple: usually done when class label is missing(when doing classification-not effective when the of missing values per attribute varies considerably a Fill in the missing value manually: tedious+ infeasible? Fill in it automatically with a global constant: e.g., unknown, a new class? ◆ the attribute mean the attribute mean for all samples belonging to the same class smarter the most probable value: inference-based such as Bayesian formula or decision tree 8 同济大学软件学院 ool of Software Engineering. Tongpi Unversity8 How to Handle Missing Data? ◼ Ignore the tuple: usually done when class label is missing (when doing classification)—not effective when the % of missing values per attribute varies considerably ◼ Fill in the missing value manually: tedious + infeasible? ◼ Fill in it automatically with ◆ a global constant : e.g., “unknown”, a new class?! ◆ the attribute mean ◆ the attribute mean for all samples belonging to the same class: smarter ◆ the most probable value: inference-based such as Bayesian formula or decision tree