diff --git a/analysis/img/README.md b/analysis/img/README.md
new file mode 100644
index 0000000..72f3d61
--- /dev/null
+++ b/analysis/img/README.md
@@ -0,0 +1,24 @@
+# img/
+
+Published summary charts for the README's analysis narrative (stable link
+targets, dataset-independent). These are *copies* — each run's full set of
+plots lives in `data/<run>/analysis/plots/`.
+
+| File | Chart | Source run |
+|---|---|---|
+| `protocol_averages.png` | Per-protocol average gradient values, ascending | synthetic_1.2.6 |
+| `gradient_averages.png` | Per-gradient averages, gaps separate the three sets | synthetic_1.2.6 |
+| `averages_histogram.png` | Distribution of protocol averages | synthetic_1.2.6 |
+
+Regenerate these from any run:
+
+```bash
+python3 scripts/univariate_analysis.py data/synthetic_1.2.6/readings.csv --img
+```
+
+(`--img` with no argument publishes to this directory; `--img <dir>` targets
+another one. The corresponding summary statistics are written to the run's
+`analysis/reports/univariate_summary.txt`.)
+
+Last refreshed: 2026-10-02, from `data/synthetic_1.2.6/` via
+`scripts/univariate_analysis.py` (`bicorder v1.2.6`).
\ No newline at end of file
diff --git a/analysis/img/averages_histogram.png b/analysis/img/averages_histogram.png
index 5663ab3..32fc2cd 100644
Binary files a/analysis/img/averages_histogram.png and b/analysis/img/averages_histogram.png differ
diff --git a/analysis/img/gradient_averages.png b/analysis/img/gradient_averages.png
index eda0449..13f199a 100644
Binary files a/analysis/img/gradient_averages.png and b/analysis/img/gradient_averages.png differ
diff --git a/analysis/img/protocol_averages.png b/analysis/img/protocol_averages.png
index 8043a31..e784dab 100644
Binary files a/analysis/img/protocol_averages.png and b/analysis/img/protocol_averages.png differ