diff --git a/reference/constraints/Collection.rst b/reference/constraints/Collection.rst
index 733b3b9144b..39f2b91ed6b 100644
--- a/reference/constraints/Collection.rst
+++ b/reference/constraints/Collection.rst
@@ -38,8 +38,8 @@ of a collection individually. Take the following example::
     class Author
     {
         protected $profileData = array(
-            'personal_email',
-            'short_bio',
+            'personal_email' => '',
+            'short_bio' => '',
         );
 
         public function setProfileData($key, $value)
@@ -80,8 +80,8 @@ following:
              * )
              */
              protected $profileData = array(
-                 'personal_email',
-                 'short_bio',
+                 'personal_email' => '',
+                 'short_bio' => '',
              );
         }