Considering the total ratings of a game compared to the median number of ratings is there to normalize the rank. Three of the four games ranked lower than Arkham had more total ratings than Arkham. In fact, one game had almost twice as many ratings. The system is in place to prevent a game with few ratings to skew the results. The ParserComp ratings were pretty evenly rated.
All of the games were excellent. Very few score points separated many of the games.