Gesture Analysis

 First, is Arthur Dent. In this gesture, he feels confused and not sort of like, "I don't know what's going on". It reflects his character rather well- he's not very bright and rarely in the loop.

Second is The Doctor, from Doctor Who. His shrug is very smug and confident. It's clearly an answer to someone's question, a "I know, but I'm not telling".

Third is Andy from Parks and Rec. He's clearly grinning- something funny is happening and he's giving an "oh, I don't know" kind of shrug. It's very in line with his character, a sort of funny man type character.