What causes the pay gap between men and women? A little theory

 
The pay gap is partly caused by compositional and structural differences between the groups of men and women by age, level of education, position and years of experience. These are the (objective) causes of the pay gap deriving from the structural differences between the genders. The other part of the pay gap which cannot be explained by these factors is the result of the subjectivity of the employer (discrimination or remuneration effect).