Classification/regression model training - Progress and termination feedback

Users have found the training process cumbersome mainly concerning visibility of system status. This is a major usability problem that has been observed across different user interventions.

In many occurrences in which the users recorded a medium-to-large amount of data, they could not understand whether the training process was crashing or just taking to long. In some cases it led them to terminated the browser window.

Recommendation: Implement asynchronous event notification in the training method (e.g., client code should subscribe to an event with a handler that reports progress and/or termination)