There is a whole field dedicated to this kind of study, namely sociolinguistics (see [1] for a short summary of the seminal experiment). Sociolinguistics study

There is a whole field dedicated to this kind of study, namely sociolinguistics (see [1] for a short summary of the seminal experiment). Sociolinguistics study surface variations in language use that cannot be accounted by dialectology only (i.e. geographical factors) among speakers of the same language. There are clusters among linguistics uses, and it turns out they map to clusters in the space of social practices. For what I have studied of the field (not that much), it seems most of the time the variation is driven by the desire to belong or show you belong to the community of the users of the trait you adopt. It's said to be "inconscious" (pretty much like my masterful ability a handling language), but at the same time the subjects at hand can arrive at the same conclusions with the help of some introspection. What's uncanny here is that having a goatee doesn't make you belong to any social group you could think of explicitly and enjoy belonging to. I guess the relationship is mostly driven by a mix of physionomical traits (gender + age) and the fact they correlate well to having a goatee (which isn't a tiny class anyway). Or there are indeed "deep" social structures to which we belong and are yet unable to identify. [1] http://all-about-linguistics.group.shef.ac.uk/branches-of-linguistics/sociolinguistics/research-in-sociolinguistics/william-labov-marthas-vineyard/ http://all-about-linguistics.group.shef.ac.uk/branches-of-li... Edit: there may well be an immense data trove hidden in people's voice. That could be a very useful way to enrich datasets internally a bit like recommendation engines work: if my neighbour speaks like I do, then he must enjoy the same things as I.