In social science research, highest education level attained would refer to the most advanced grade or degree achieved by an individual-for some individuals, it may be a grade in grade school, and for other individuals, it may be a Bachelor' s Degree, a Master' s Degree, or Ph  D  (which is considered the highest education level)  A recent study has shown a strong correlation between highest education level attained and proficiency in chess
Another result, studied at many points throughout the 20th century, shows a marked positive correlation between highest education level attained and income level
An individual's proficiency at chess rises consistently during that individual's years of school, and levels off once that individual has finished her years of formal education.