/**
  *
  * @param <type> $pProperty
  * @return <type>
  */
 public function get_effect($pProperty, $pString = FALSE)
 {
     $eff = $this->get_efficiency($pProperty);
     if (is_null($eff)) {
         return $pString ? '(unknown)' : NULL;
     }
     $eff_factor = Ultimatum_Model_Ultgroups::eff_factor($eff);
     $size = $this->get_size($pProperty);
     if (is_null($size)) {
         return $pString ? '(unknown)' : NULL;
     }
     return Ultimatum_Model_Ultgroups::effect($size, $eff_factor, $pString);
 }