STEM: science, technology, engineering and mathematics. This is misleading since really, it should be *natural* science and not social. Psychology is a natural science (the social aspects are more covered in sociology) since it's an offshoot or specialisation of biology which focuses on behavioural mechanics and conditions (and the underpinning causes) rather than their outward effect on society. Economics is very hit or miss in the UK by the way, some economics courses are very mathematical, in fact are practically applied maths degrees (Cambridge, LSE, UCL etc) whilst others are substantially less maths heavy. Crucially economics itself is a social study so it doesn't matter if STEM is used in it.