context: A man is signing a guitar, whose owner is smiling and has a hat with lights attached to it.
hypothesis: It is highly unlikely that a famous singer is autographing a fan's guitar.
valid_hypothesis: Chances are about even that a famous singer is autographing a fan's guitar.
invalid_hypothesis: It is highly unlikely that a famous singer is autographing a fan's guitar.
hypothesis_assertion: A famous singer is autographing a fan's guitar.