Let me try:
- As we know, the first learning step is applied to cards whose first rating is
again. And the second learning step is applied to cards whose first rating isgood. The average of the 1st and 2nd steps is applied to card whose first rating ishard. - The stability of
Againis recommended setting as the 1st learning step if your desired retention is 90%. And if the stability ofGoodis less than 0.5d and you are using the default desired retention, the 2nd learning step can be set as the stability ofGood. - If the stability of
Hardis less than the average of stabilities ofAgainandGood, I recommend lowering the 2nd learning step to 2x stability ofHardto ensure you have 90% retention on cards whose first rating ishard.