[SPARK-19787] Different default regParam values in ALS

• Type: Improvement
• Status: Resolved
• Priority: Trivial
• Resolution: Fixed
• Affects Version/s: 2.0.0, 2.0.1, 2.0.2, 2.1.0
• Fix Version/s: 2.2.0
• Component/s: MLlib
• Assignee: Unassigned
• Reporter: Vasilis Vryniotis
• Created: 01/Mar/17 13:59
• Updated: 16/May/17 10:08
• Resolved: 01/Mar/17 18:55

Description

In the ALS method the default values of regParam do not match within the same file (lines 224 and 714). In one place we set it to 1.0 and in the other to 0.1.

We can change the one of train() method to 0.1. The method is marked with DeveloperApi so it should not affect the users. Based on what I saw, whenever we use the particular method we provide all parameters, so the default does not matter. Only exception is the unit-tests on ALSSuite but the change does not break them.

This change was discussed on a separate PR and mlnick suggested to create a separate PR & ticket.

Issue Links

• relates to: SPARK-20506 ML, Graph 2.2 QA: Programming guide update and migration guide
• links to: [Github] Pull Request #17121 (datumbox)