How people learn to program9 min read

Distributed Practice in Verbal Recall Tasks: A Review and Quantitative Synthesis

Nicholas J. Cepeda, Harold Pashler, Edward Vul, John T. Wixted, Doug Rohrer · 2006 · Psychological Bulletin 132(3), 354–380

A meta-analysis of 317 experiments: spreading practice out beats cramming, and the best gap grows with how long you need to remember.

Read the paper ↗doi:10.1037/0033-2909.132.3.354 ↗

The short version

→Across 839 comparisons, practice sessions separated by a gap produced better long-term recall than the same practice massed together.
→The optimal gap is not fixed — it scales with the retention interval. Want to remember for a month? Space by days, not minutes.
→Spacing effects are large and robust across ages, materials and test formats; the authors call it one of the most reliable findings in memory research.
→This is the evidence behind every ‘spaced repetition’ system, including Saasworld's review intervals.

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