{
  "accessed": "2026-10-29",
  "scope": "Selected published summary statistics; no Stadiy outcome data",
  "ai_tutoring": {
    "source": "Kestin et al. (2025), Results: Learning gains: post-test scores",
    "url": "https://pmc.ncbi.nlm.nih.gov/articles/PMC12179260/",
    "doi": "10.1038/s41598-025-97652-6",
    "metric": "Reported median post-test score, raw points",
    "active_learning": 3.5,
    "ai_tutor": 4.5,
    "pooled_pretest_median": 2.75,
    "active_learning_observations": 174,
    "ai_tutor_observations": 142,
    "eligible_participants": 194,
    "uncertainty": "Median confidence intervals not extracted; plot contains no error bars"
  },
  "retrieval": {
    "source": "Roediger & Karpicke (2006), Experiment 2, Final Tests and Figure 2",
    "url": "https://psychology.ecu.edu/wp-content/pv-uploads/sites/216/2019/03/Roediger-Karpicke-2006.pdf",
    "doi": "10.1111/j.1467-9280.2006.01693.x",
    "metric": "Mean percentage of idea units recalled",
    "conditions": ["4 study periods", "3 study + 1 recall", "1 study + 3 recalls"],
    "five_minutes": [83, 78, 71],
    "one_week": [40, 56, 61],
    "participants": 180,
    "uncertainty": "Means transcribed from results text; numerical standard errors not extracted"
  },
  "spacing": {
    "source": "Latimier, Peyre & Ramus (2021), published abstract",
    "url": "https://link.springer.com/article/10.1007/s10648-020-09572-8",
    "doi": "10.1007/s10648-020-09572-8",
    "metric": "Reported Hedges g, standardized effect",
    "spaced_vs_massed": 0.74,
    "expanding_vs_uniform": 0.034,
    "studies_total": 29,
    "effect_sizes_subset_1": 39,
    "effect_sizes_subset_2": 54,
    "uncertainty": "Abstract-reported point estimates only; confidence intervals not extracted"
  },
  "guardrails": {
    "source": "Bastani et al. (2025), abstract and main results",
    "url": "https://pmc.ncbi.nlm.nih.gov/articles/PMC12232635/",
    "doi": "10.1073/pnas.2422633122",
    "base_assisted_practice_relative_percent": 48,
    "tutor_assisted_practice_relative_percent": 127,
    "base_unassisted_exam_relative_percent": -17,
    "tutor_unassisted_exam": "No statistically distinguishable improvement over control",
    "note": "Relative changes, not percentage-point differences"
  }
}