Hitch-hiking ratings system

On your PDA you see that there is a hitchhiker waiting on the way from you house going to the same part of the city as you. You take a look at their ratings.

smell: 10 conversation: 7 friendliness: 8 punctuality: 8

You decide, not being much of a conversationalist yourself, that you and a person who get a seven for conversation might get along. So you pick them up, the system is notified(so if you don't rate the trip after it occurs, the police will eventally be notified). Whallah, hitchhiking becomes safe and conveniant, and you get to drive in the carpool lane!