Evidence-based spaced repetition schedules for vocabulary
Evidence-based spaced repetition schedules for vocabulary typically involve reviewing words at increasing intervals based on the forgetting curve, a concept introduced by Hermann Ebbinghaus. A common effective schedule starts with a first review about 1 day after initial learning, then subsequent repetitions spread out over days and weeks, such as on days 1, 6-7, 14-16, 30-35, 60-66, 150, and up to a year. This expanding interval method leverages the spacing effect, where spaced reviews lead to better long-term retention by challenging memory retrieval progressively. Usually, around 7 repetitions spaced over increasing intervals are sufficient for lifelong retention of vocabulary. These intervals can be personalized and optimized by algorithms analyzing individual forgetting curves, combining spaced repetition with active recall to maximize learning efficiency and memory stability.
Key points in evidence-based spaced repetition vocabulary schedules include:
- Initial repetition within 24 hours after learning a word.
- Subsequent reviews spaced about a week later, then two weeks, then a month, and continuing with increasing intervals.
- A multiplying interval factor of around 2 to 2.5 (ease factor), where each review interval is roughly double the previous one.
- The schedule adapts to the learner’s performance and task difficulty, with more frequent reviews for harder or less familiar words.
- Neuroscientific findings show spaced repetition strengthens memory via retrieval and reconsolidation processes, making memories more durable.
- Studies demonstrate spaced repetition outperforms massed practice (cramming) for vocabulary retention and transfer of knowledge.
An example effective spaced repetition schedule for vocabulary based on research is: Day 0 (initial learning), Day 1, Day 6-7, Day 14-16, Day 30-35, Day 60-66, Day 150, Day 360.
This approach balances efficiency with effectiveness by expanding intervals to reduce review frequency while maintaining strong memory retention. 1, 2, 3, 4, 5, 6