[jQuery] Help with change event

I am interested in the event change, and am looking at
http://docs.jquery.com/Events/change.

 $("select").change(function () {
          var str = "";
          $("select option:selected").each(function () {
                str += $(this).text() + " ";
              });
          $("div").text(str);
        })
        .change();

It all makes sense except for the very last change().  Can anyone
explain the purpose of this line?

Thank you