The science behind Lumi

The guides, one topic per page

• How to study effectively, according to the researchIn the 2013 review by Dunlosky and colleagues, only two of ten study techniques earned a high utility rating, practice testing and spreading your study sessions out over time (Dunlosky et al., 2013). Rereading, highlighting and summarizing were rated low.
• Active recall, why quizzing yourself beats rereadingIn experiment 2 by Roediger and Karpicke (2006), students who read a text and then quizzed themselves three times remembered 61% of the ideas a week later, against 40% for those who reread it four times (Roediger and Karpicke, 2006). Forcing yourself to pull information out of memory fixes it better than looking at it again.
• Spaced repetition, how long to wait between two reviewsIn the study by Cepeda and colleagues, the best gap between two sessions is about 20 to 40% of the time before the test when the exam is a week away, and about 5 to 10% when it is a year away (Cepeda et al., 2008). A meta-analysis of 839 measures confirms that spacing beats massing (Cepeda et al., 2006).
• What Ebbinghaus’s forgetting curve really showsIn 1885 Ebbinghaus measured the time saved when relearning a list, 58.2% after 20 minutes and 21.1% after 31 days (Ebbinghaus, 1885). These are time savings, not percentages of memory, and Dros found a similar curve in 2015 (Murre and Dros, 2015).
• Does learning by teaching work? What research says about the protégé effectPreparing to teach a text led to fuller, better organized recall in Nestojko and colleagues (2014). But Koh and colleagues (2018) found that the benefit comes mostly from retrieval, which means explaining without your notes.
• Why rereading your notes is not enoughRereading gives you the feeling of knowing without guaranteeing you can retrieve the information. In the 2006 study by Roediger and Karpicke, students who reread four times remembered 40% of the ideas a week later, against 61% for those who quizzed themselves (Roediger and Karpicke, 2006).
• How to make flashcards that actually workA good card asks a question and makes you produce the answer from memory, because the meta-analysis by Rowland (2014) found that recall tests give a bigger benefit than multiple choice. And in Kornell (2009), one large deck studied with spacing beat four small decks studied in one block.
• How to make a study schedule before an examPlace your sessions at gaps that grow with the time before the exam, about 20 to 40% of the time left if the exam is a week away (Cepeda et al., 2008). Rawson and Dunlosky advise recalling an idea correctly 3 times in the first session, then relearning it 3 times at widely spaced intervals (Rawson and Dunlosky, 2011).
• Does cramming the night before an exam work?In Kornell’s study, spacing was more effective than cramming the night before for 90% of the participants, even though 72% thought after the first session that massing worked better (Kornell, 2009). If you have no choice, you can still do better than rereading all night.
• Does interleaving, or mixed practice, really help you study?Interleaving means mixing problem types instead of doing them in blocks. In Rohrer and Taylor (2007), mixing math problems improved results on a delayed test compared with grouping them by type.
• Is highlighting your notes actually useful?In the review by Dunlosky and colleagues, published in 2013, highlighting or underlining is one of the five techniques rated low utility out of the ten compared (Dunlosky et al., 2013). That does not mean your highlighter is banned, only that it should not be your main method.
• Sleep and memory, why sleeping after you study mattersIn the study by Jenkins and Dallenbach (1924), people forgot less when they slept after learning than when they stayed awake. Rasch and Born (2013) summarise that sleep takes part in the consolidation of memories.

Every study cited

Each reference was checked before publishing. Links go to the article or its DOI.

1. Bjork, Dunlosky, Kornell (2013). Self-regulated learning. Beliefs, techniques, and illusions. Annual Review of Psychology, 64. doi.org/10.1146/annurev-psych-113011-143823
2. Cepeda, Pashler, Vul, Wixted, Rohrer (2006). Distributed practice in verbal recall tasks. A review and quantitative synthesis. Psychological Bulletin, 132(3). doi.org/10.1037/0033-2909.132.3.354
3. Cepeda, Vul, Rohrer, Wixted, Pashler (2008). Spacing effects in learning. A temporal ridgeline of optimal retention. Psychological Science, 19(11). doi.org/10.1111/j.1467-9280.2008.02209.x
4. Chase, Chin, Oppezzo, Schwartz (2009). Teachable agents and the protégé effect. Increasing the effort towards learning. Journal of Science Education and Technology, 18(4). doi.org/10.1007/s10956-009-9180-4
5. Dunlosky, Rawson, Marsh, Nathan, Willingham (2013). Improving students' learning with effective learning techniques. Psychological Science in the Public Interest, 14(1). doi.org/10.1177/1529100612453266
6. Ebbinghaus (1885). Über das Gedächtnis (Memory. A contribution to experimental psychology). Duncker und Humblot, Leipzig. psychclassics.yorku.ca/Ebbinghaus/index.htm
7. Fiorella, Mayer (2013). The relative benefits of learning by teaching and teaching expectancy. Contemporary Educational Psychology, 38(4). doi.org/10.1016/j.cedpsych.2013.06.001
8. Jenkins, Dallenbach (1924). Obliviscence during sleep and waking. The American Journal of Psychology, 35(4). doi.org/10.2307/1414040
9. Kang (2016). Spaced repetition promotes efficient and effective learning. Policy Insights from the Behavioral and Brain Sciences, 3(1). doi.org/10.1177/2372732215624708
10. Karpicke, Blunt (2011). Retrieval practice produces more learning than elaborative studying with concept mapping. Science, 331(6018). doi.org/10.1126/science.1199327
11. Karpicke, Butler, Roediger (2009). Metacognitive strategies in student learning. Do students practise retrieval when they study on their own?. Memory, 17(4). doi.org/10.1080/09658210802647009
12. Karpicke, Roediger (2008). The critical importance of retrieval for learning. Science, 319(5865). doi.org/10.1126/science.1152408
13. Koh, Lee, Lim (2018). The learning benefits of teaching. A retrieval practice hypothesis. Applied Cognitive Psychology, 32(3). doi.org/10.1002/acp.3410
14. Kornell (2009). Optimising learning using flashcards. Spacing is more effective than cramming. Applied Cognitive Psychology, 23(9). doi.org/10.1002/acp.1537
15. Murre, Dros (2015). Replication and analysis of Ebbinghaus' forgetting curve. PLOS ONE, 10(7), e0120644. doi.org/10.1371/journal.pone.0120644
16. Nestojko, Bui, Kornell, Bjork (2014). Expecting to teach enhances learning and organization of knowledge in free recall of text passages. Memory and Cognition, 42(7). doi.org/10.3758/s13421-014-0416-z
17. Rasch, Born (2013). About sleep's role in memory. Physiological Reviews, 93(2). doi.org/10.1152/physrev.00032.2012
18. Rawson, Dunlosky (2011). Optimizing schedules of retrieval practice for durable and efficient learning. How much is enough?. Journal of Experimental Psychology. General, 140(3). doi.org/10.1037/a0023956
19. Roediger, Karpicke (2006). Test-enhanced learning. Taking memory tests improves long-term retention. Psychological Science, 17(3). doi.org/10.1111/j.1467-9280.2006.01693.x
20. Rohrer, Taylor (2007). The shuffling of mathematics problems improves learning. Instructional Science, 35(6). doi.org/10.1007/s11251-007-9015-8
21. Rowland (2014). The effect of testing versus restudy on retention. A meta-analytic review of the testing effect. Psychological Bulletin, 140(6). doi.org/10.1037/a0037559
22. Slamecka, Graf (1978). The generation effect. Delineation of a phenomenon. Journal of Experimental Psychology. Human Learning and Memory, 4(6). doi.org/10.1037/0278-7393.4.6.592