Forced marriages or early marriages are often considered types of slavery. Forced marriage continues to be practiced in parts of the world including some parts of Asia and Africa and in immigrant communities in the West. Sacred prostitution is where girls and women are pledged to priests or those of higher castes, such as the practice of Devadasi in South Asia or fetish slaves in West Africa. Marriage by abduction occurs in many places in the world today, with a national average of 69% of marriages in Ethiopia being through abduction. Economists have attempted to model the circumstances under which slavery (and variants such as serfdom) appear and disappear. One observation is that slavery becomes more desirable for landowners where land is abundant but labour is scarce, such that r