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+# Stroop Example (Chapter 13)
+
+**Data**: `data/synthetic/psych_stroop_*.csv` generated by `scripts/sim_stroop.py`.
+
+**Run**:
+```bash
+python scripts/sim_stroop.py
+python scripts/ch13_stroop_within.py --save-plots
+```
+
+**Columns** (trials):
+- subject: int (1–60)
+- condition: congruent|incongruent
+- trial: 1..100 per condition
+- rt_ms: reaction time (ms)
+- correct: 0/1
+
+Outputs in `outputs/`: subject-means spaghetti & trial-level violins.
+