diff --git a/macs2.wdl b/macs2.wdl
index 76c615d2d94793ec20933a4348d2f8dcb400e2e2..9880c944a6b0942effc88472f64487b165d15d39 100644
--- a/macs2.wdl
+++ b/macs2.wdl
@@ -14,7 +14,7 @@ task PeakCalling {
         --treatment ${sep = ' ' bamFiles} \
         --outdir ${outDir} \
         --name ${sampleName} \
-        ${default="false" true='--nomodel' false='' nomodel}
+        ${default=false true='--nomodel' false='' nomodel}
     }
 
     output {