Machine Learning for Business
Karolis Urbonas
Head of Machine Learning & Science, Amazon
Some models perform poorly (make sure you review test performance, not training):
Low precision
Low recall
Large error
Low precision - a lot of misclassified items in the class of interest = a lot of false positives
Example - only 10% of customers identified as likely to purchase actually purchased the product
Low recall - only a small fraction of all observations in the class have been correctly captured (recalled) by the model
Example - only 25% of all fraudulent transactions identified by the model
Large error - large differences between predicted and actual values
Example - the average error for the customer satisfaction rating prediction is 3.5 units or 70% in percentage points
Q: How to test the models correctly?
A: Run tests / experiments to validate their performance e.g. churn prevention emails, product promotions, manual machine maintenance, manual transaction review
Machine Learning for Business