* Actions($user_id,$session_id);
  - view($itemid,$itemdesc,$itemurl);
  - buy($itemid,$itemdesc,$itemurl);
  - rate($itemid,$itemdesc,$itemurl,$rvalue);
  
* Recommendations($user_id);
  - alsoViewed($itemid,$n=10);
  - alsoBought($itemid,$n=10);
  - ratedGood($itemid,$n=10);
  - recForUser($user_id=$this->userid,$n=10);
  - relatedItems($itemid,$n=10);
  
* Rankings();
  - mostViewed($timeRange="ALL",$n=10);
  - mostBought($timeRange="ALL",$n=10);
  - mostRated($timeRange="ALL",$n=10);
  - bestRated($timeRange="ALL",$n=10);
  - worstRated($timeRange="ALL",$n=10);