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+# PyStatsV1 Docs
+
+- Chapter 12 — Diagnostics  
+  - `scripts/ch12_diagnostics.py`
+- Chapter 13 — Within-Subject Stroop  
+  - Data: `data/synthetic/psych_stroop_*`  
+  - Run: `scripts/sim_stroop.py`, `scripts/ch13_stroop_within.py --save-plots`
+- Chapter 13 — Fitness 2×2 Mixed (this chapter)  
+  - Data: `data/synthetic/fitness_*`  
+  - Run: `scripts/sim_fitness_2x2.py`, `scripts/ch13_fitness_mixed.py --save-plots`
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 # Fitness 2×2 Mixed Example (Chapter 13)
 
 **Data**: `data/synthetic/fitness_subjects.csv`, `data/synthetic/fitness_long.csv`  
-*(metadata JSON is generated and ignored by git)*
+*(metadata JSON is generated on the fly and ignored by git).*
 
 ## Run
 ```bash