Add demo showing clinical context reranking for AIDS differentials

README.md

@@ -163,6 +163,36 @@ results = retrieve_and_rerank(
 )
 ```
 
+## Demo: Cross-Encoder Reranking
+
+```python
+from sentence_transformers import CrossEncoder
+import numpy as np
+
+model = CrossEncoder('matulichpt/radlit-crossencoder')
+
+query = "What causes ring-enhancing brain lesions in AIDS patients?"
+
+# Candidates from bi-encoder retrieval (simulated)
+candidates = [
+    "In AIDS, toxoplasmosis shows ring-enhancing lesions in basal ganglia. CNS lymphoma is typically periventricular.",
+    "Brain metastases occur at gray-white junction and may show ring enhancement.",
+    "Glioblastoma is the most common primary brain malignancy.",
+]
+
+# Score each candidate
+pairs = [[query, doc] for doc in candidates]
+scores = model.predict(pairs)
+
+# Rank by relevance
+ranked = sorted(zip(candidates, scores), key=lambda x: x[1], reverse=True)
+print(f"Top result: {ranked[0][0][:80]}...")
+print(f"Score: {ranked[0][1]:.2f}")
+# The AIDS-specific answer ranks first despite shorter text
+```
+
+The cross-encoder correctly prioritizes the clinically relevant answer about AIDS-specific differentials.
+
 ### Temperature Calibration
 
 **Important**: For optimal performance in score fusion, apply temperature scaling: