DISTRIBUTION OF CONTENT BASED ON MACHINE LEARNING BASED MODEL BY AN ONLINE SYSTEM

An online system performs distributes content items received from content provider systems. The online system selects content items for sending to users based on values associated with user actions performed by users responsive to accessing the content items. The online system uses machine learning based models for predicting expected values of user actions associated with content items. The machine learning model may be a neural network model with a shared component and a plurality of dedicated components, each dedicated component trained to predict a term used for determining the expected value. The neural network is trained using labeled data where the labels are normalized expected values. The online system performs calibration of the predicted values to determine a denormalized value for use in selecting content items for delivery to users.