fix: use 0.15 as AI detection threshold in demo

app.py

@@ -179,8 +179,8 @@ def detect_ai_text(text):
 
     score, entropy_score, ce_score = detector.compute_score(text)
 
-    # Based on the paper's findings, we use 0.19 as the threshold
-    is_ai_generated = score < 0.19
+    # Threshold for AI vs human (demo setting)
+    is_ai_generated = score < 0.15
 
     # Format the result with more detailed information
     result = f"""
@@ -190,7 +190,7 @@ def detect_ai_text(text):
 - **CE Score**: {ce_score:.4f}
 
 ### Interpretation
-- **Threshold**: 0.19 (scores below this are likely AI-generated)
+- **Threshold**: 0.15 (scores below this are likely AI-generated)
 - **Current Score**: {score:.4f}
 """
     if is_ai_generated: