Clarify threshold documentation

Author: stevebauman

README.md

@@ -137,7 +137,7 @@ echo $redacted;
 
 ## Thresholds
 
-The classifier uses a default threshold of `0.5`. The threshold is the minimum confidence score an entity must meet before it is returned. Increasing the threshold returns fewer, higher-confidence entities, while decreasing it may return more entities with lower confidence.
+The classifier uses a default threshold of `0.5`. Only entities with a confidence score equal to or greater than the threshold will be returned.
 
 You may provide a threshold at runtime when classifying text: