Some people laugh out of anxiety after saying something stupid.
Other people laugh out of provocation after saying something stupid.
How do you tell the difference?
Let me take a stab at it: people anxious about having said a stupid thing are probably less angry then surprised at themselves, and who ever found their said thing stupid. They may be anxious because of having been found out, they are suffering two emotions simultaneously: shame, and fear (of what the consequences could be)
Other people. With a provocative laughter, are conveying a a sense of denial and anger at the same time, probably with a pronounced ironic grin…
Therefore the former may exhibit a nervous, shallow laugh, whereas the later a sustained, I know better kind of pronounced and artificial belch like Ha Ha… Just a guess.
You tell by their body language.
Those are pretty different emotional states, one should be able to read them fairly well.
Perhaps by the decibel level - the anxious laugh would be much lower than the provoked laugh.
I agree with Moreno.
There will probably be signs of embarrassment in the former, blushing, shrinking from the conversation that immediately follows.
In the latter, the person would probably make more eye contact and appear intent on listening to how people respond.
Cool. I suspect, however, that Daktoria has something specific in mind, something that may tweak the issue.
Daktoria,
with bated breath I await.
Its been a week since she did the one original post. At least you are not holding your breath. 
Is she a she? I didn’t know that.
Yea, pretty certain she is a she, she could be a he, I dunno now. How about generic - shehe or heshe?
I thought that daktoria was a he too for some unknown reason. You can’t necessarily go by the "ia"s kristy.
But daktoria may be a female with a strong intellectual male center…not meaning gay in the slightest. 
Can I get an example of this?
I Believe I have experienced this. Someone says something provocative - say, slavery was actually not that bad - and then they laugh in a sort of self-congratulatory way. Sort of expressing a kind of ‘I had the balls to say that, that’s right.’
Well that depends upon who they say it to and how. Two people close friends used to giving each other pokes and prods, one white one black. The laugh would be provocative with humor. A friendly fight commences.
I was giving it as an example of laughing after saying something provocative and stupid. So I am not sure what your Point is. Sure, it could also be a joke between friends. But that’s not really relevent. I was trying to present Gib with a scenario where one can laugh while provoking, rather that laughing out of nervousness. You are now giving a third kind of scenario, which is fine, but it really doesn’t affect my example.
Yea I know. It popped into my head and just typed it. Long day, sorry about that.
Oh, I’ve seen that.
We were at the office one day asking people to donate to a charity. One guy said “Nope, I’m too busy…” then walked down the hall and said “I’m watching TV, ha! ha! ha!”