Neurotic? Extroverted? Disagreeable? Political campaigns have an ad for you.

I had been talking to Alexander Nix, the CEO of the data analytics firm Cambridge Analytica, for only a few minutes before he noticed my leopard-print shoes, and complimented them.
“I’ll put it in your personality file,” Nix joked.
“Does this mean you can already predict my personality?” I asked warily.