No. 4:
This is a complex question, highly dependent upon who in public we are talking about, and how we define "nice." For "people in public" I am going to look at the following categories: coworkers with whom I am not already friends; service personnel (waitstaff, checkers, auto mechanics, salespeople, etc.); total strangers (people in elevators, people in lines at the grocery store, fellow bar patrons, etc.); and "peacekeepers" (police officers, park officials, bouncers, etc.)
Coworkers with whom I am not already friends:
I can't detect a gender difference. Nobody is nicer to me than they are to, say, Bob.
Service personnel:
Those attempting to sell me traditionally female items and services tend to be friendlier to me than to men, though they aren't mean to the men; they just tend to ignore their existence. Those attempting to sell me traditionally male items and services pretty much treat me just like the female item/service sellers treat the men. Those attempting to sell me gender-neutral items and services vary so wildly by personality that I can't detect a pattern either way.
Total strangers:
Sober ones are nicer to me than to men, though again, they aren't generally mean to the men; they usually just ignore them more. Drunk ones are hideously obnoxious, though I imagine they think they're being "nicer." For instance, when I'm out at a bar with my husband, nobody talks to him and a few people, more often male than female but still some female, talk a little to me. He goes to the bathroom, I have a series of guys practically climbing on my lap and making extremely personal remarks to me while he's gone. When I go to the bathroom, nobody, male or female, interacts with him while I'm gone.
"Peacekeepers:"
Much nicer to me than to the men.
