How to determine '+ variable +' in var url string?

[BaseballGraphs]

Hello,

I am trying to determine what the appropriate variable is to place between plus (+) tags in in a javascript var url string. For instance I have the following code:

<script>
   function refreshData() {
   var url = "/pulldata.php?p=" + tags + "&s=" + statistic + "";
 
// rest of js
</script>
 

Essentially, what is the definition of + tags + and + statistic + and how do you determine what variables they are supposed to be?

[Dormilich]

tags and statistic seem to be 2 global variables.

[BaseballGraphs]

How would I define the global variable for $statistic_id from this bit of code:

<div id="playerstats">
<table width="265px" border="0" >
<? $i = 0; foreach ($combine as $statistic_id => $stat_values): ?>
<tr>
<td style="vertical-align:middle; font-size : 11px;">
  <input type="checkbox"  id="checkbox_<?= $statistic_id; ?>" <?= $i==0 ? 'checked="checked"' : null; ?> />
  <label for="checkbox_<?= $statistic_id; ?>"><?= getStatisticFromId ( $statistic_id ); ?></label>
</td>
</tr>
<? $i++; endforeach; ?>
</table>
<script>
</div>
 

$statistic_id is a variable number that is associated with the checkbox. When someone clicks a new checkbox they are effectively selecting a new $statistic_id. I need to define $statistic_id as a global variable so that I can incorporate it into my AJAX. Please see this code below:

 function refreshData() {
   var pid = <?= $_GET['p']; ?>;
   var statistic_id = ???;
   var url = "/pulldata.php?p=" + pid + "&s=" + statistic_id + "";
   $.getJSON( url,
   function(data){
     for ( pid in data ) {
       for ( statistic_id in data[ pid ] ) {
         console.log( data[ pid ][ statistic_id ] );
         drawLineOnGraph( data[ pid ][ statistic_id ] );
      }
    }
   } );
  }
 

If you know of a way to make $statistic_id a global variable that I can incorporate into my AJAX that would be helpful. Thanks.