analytics - piwikTracker 未定义

Question

有这个页面：

<script src="http://website.byethost4.com/jquery-1.9.0.min.js"></script>

<script>
$(document).ready(function(){
  $('#link').click(function(){
    piwikTracker.setCustomVariable(1, "VisitorType", "Member", "visit");
    piwikTracker.trackPageView();    
     return false;
  });
});
</script>

<a id="link" href="http://website.byethost4.com/view.php" >link</a>

Firebug->error->errors显示piwikTracker not defined. 怎么解决？piwik 安装在http://website.byethost4.com/piwik