Rolling 180/30 Walk-Forward

In this course's design, how far does each fold move forward?

• 1 day, so every day gets its own fold
• 30 days, the length of the test window
• 180 days, the length of the training window

A splitter's training sets are "supersets of those that come before them". What kind of window is that?

• Rolling
• Expanding
• Purged