Human Capital is Becker's classic study of the consequences of investing in a person's knowledge and skills. According to his theory, investment in an individual's education and training is similar to business investments in equipment. Becker looks at the economic effects of investment in education on employment and earnings, and shows how his theory measures the incentive for such investment. The human capital approach also allows for determining the costs and returns from college and high school education. Another part of the study explores the relation between on-the-job experience, age, and earnings.