diff --git a/README.md b/README.md
index 16e2194..662a40b 100644
--- a/README.md
+++ b/README.md
@@ -68,7 +68,7 @@ You may also want to disable metrics and the green-red color scheme by
 parameter:
 
 ~~~
-ocrd-dinglehopper -I ABBYY-FULLTEXT,OCR-D-OCR-CALAMARI -O OCR-D-OCR-COMPARE-ABBYY-CALAMARI -p '{"metrics": false}'
+ocrd-dinglehopper -I ABBYY-FULLTEXT,OCR-D-OCR-CALAMARI -O OCR-D-OCR-COMPARE-ABBYY-CALAMARI -P metrics false
 ~~~
 
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