I've seen a lot of stuff about Twitter's language inference and I've got to say that the secondary languages can't be based on behavior.pic.twitter.com/g9WCua0Fcx
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I don't know where Latvian, Welsh, etc. come from. I've never even visited those countries.
On the other hand, I speak Spanish, and have some skill in German, Czech, and Turkish and have posted & follow accounts in those languages.
I spent a bunch of time so far this year in Czechia and Germany receiving local promoted tweets in those languages. So what's the logic?
These are the languages Bing translator thought tweets were in, apparently.
But perhaps you've conversed with followers who have, or who speak it?
Simple population numbers suggest that something like Spanish should be way at the top if that were the case.
I meant, maybe that's one of the factors in the mix? e.g. LinkedIn uses your language preferences as an input to your connections graph.
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