Simple code works in JSFiddle but not on a page

Simple code works in JSFiddle but not on a page

I have a simple Confirm on a tick box - http://jsfiddle.net/apWUj/1/ - but on a page on my server nothing.

Am I mssing some thing that JSFiddle includes - a wrapper of some sort

<html>
  <head>
 
<link type="text/css" href="css/ui-lightness/jquery-ui-1.8.10.custom.css" rel="stylesheet" />   
<script type="text/javascript" src="js/jquery-1.8.2.js"></script>    

 <script>
$('input.delcal:checkbox').click(function(){
    var checked = $(this).is(':checked');
    if(checked) {
        if(!confirm('Are you sure you want to resume use of this program?')){        
            $(this).removeAttr('checked');
        }
    } else if(!confirm('Are you sure you want to discontinue this program?')){
        $(this).attr("checked", "checked");
    }
});
</script>
 </head>
  <body>
 <div>
     <table>
        <tr>
              <td align="center">
       
              <input type="checkbox" name="chkdelrow" id="chkdelrow" class="delcal">
                  
              </td>
        </tr>
     </table>
  </div>
  </body>
</html>