I have taken several online personality theory tests and all have confirmed that my central personality dimension is extrovert 
Do you believe those are pretty accurate?
Honestly, if there are precise factors when measuring beer, then why not on personality measurements
That's one of the best answers I've ever heard when questioning those type of tests. I'm impressed. I agree though. I've taken them before and remember being in agreement with the results also.
All these personality tests have some direct or indirect origin in Linguistic development of Genie a child who could not acquire language skills