“…Let's consider characteristics of service values. According to Kosaka ((Kosaka, Doan, Shirahada and Wang, 2013), (Doan, Shirahada, Kosaka and Wang, 2012)), "the value of a given service is generally determined according to the situation (e.g., people's characteristics, place, time, cost,)." That is to say, "even if the same service is provided, the service value is different due to people's characteristics or the situation."…”