FYI: various (possible) inconsistencies within psych rotations

[maxheld83]

uh, testing these rotation results is a bag of hurt.

This has nothing much per se to do with qmethod, but I thought I'd post these issues here anyway, in case anyone stumbles upon them in the future:

• stats::varimax and GPArotation::Varimax are different: http://stackoverflow.com/questions/32350891/why-are-there-differences-between-gparotationvarimax-and-statsvarimax?noredirect=1#comment52575420_32350891
• these differences get exacerbated by psych::principal (solved): http://stackoverflow.com/questions/32351780/why-are-there-differences-in-psychprincipal-between-varimax-and-varimax/32351888#32351888