Update app.py

app.py

@@ -28,7 +28,7 @@ def main():
     st.markdown("""Given an optimization problem in natural language, Ner4Opt extracts optimization related entities from free-form text. The source code for Ner4Opt is available at https://github.com/skadio/ner4opt""")
 
     option = st.sidebar.selectbox(
-        'Select the model for extracting entities',
+        'Select a lexical, semantic, or hybrid model for extracting entities',
         ('Lexical', 'Lexical Plus', 'Semantic', 'Hybrid'))
 
     text = st.text_area(