Never posted on this stack site before, so I hope I'm not being rude.
I would like to know what bias, fallacy, or combination thereof is involved in the case of treating a (probably rotating) group of people as a single person against which you judge yourself.
Positive example: the very smart members of an online forum discuss a wide range of topics. You read the forum, not paying attention to who is posting any given response, and feel lacking in intelligence by comparison to this theoretical brilliant person who has something to say about every topic. Consequentially you feel stupid.
Negative example: you walk past an ice cream shop every day and look in the window at the patrons, who are different every time. You wish you, too, could eat ice cream every day. Consequentially you over-indulge in ice cream.