resize.js

(function(w) {
  var resizeTimer
  ,   $win = $(w);
  
  // Assuming we have jQuery present
  $win.on( "resize", function() {
    
    // Use resizeTimer to throttle the resize handler
    clearTimeout( resizeTimer );
    resizeTimer = setTimeout(function() {

     /* Send the event to Google Analytics
      *
      * https://developers.google.com/analytics/devguides/collection/gajs/methods/gaJSApiEventTracking
      * _trackEvent(category, action, opt_label, opt_value, opt_noninteraction)   
      */
      _gaq.push( [ "_trackEvent", "User Actions", "Browser Resize", $win.width() + " x " + $win.height() ] );
    }, 1000);
  });
})(window);