He is a Professor of Applied Linguistics at Northern Arizona University, United States.
Jarvis obtained his Bachelor of Arts degree in linguistics at Brigham Young University in 1991.
He obtained a Master of Arts degree in applied linguistics at Indiana University Bloomington in 1993.
In 1997 he was awarded with the Doctor of Philosophy degree in linguistics at Indiana University Bloomington.
According to Jarvis's model, lexical diversity includes variability, volume, evenness, rarity, dispersion and disparity.