Why does a student majoring in English have to pay the same tuition as an engineering student with much higher earning potential? In a new working paper published by the National Bureau of Economic Research, one economist suggests looking at differential tuition—the practice of varying tuition costs across areas of study.

Using data from the Integrated Postsecondary Education Data System, Kevin M. Stange from the University of Michigan’s Gerald R. Ford School of Public Policy analyzed 50 universities that had instituted higher fees for their nursing, engineering and business majors between 1990 and 2008. Mr. Stange found that the effects of implementing differential tuition vary among groups of students and areas of study.

The share of degrees awarded in engineering and business decreased within three years after putting in place the differential tuition program. Nursing gained some graduates in spite of a boost in fees. Women and minorities were more likely to be negatively affected by increases in tuition than men and whites.

“Price does appear to be a policy lever through which state governments can alter the field composition of the workforce they are training with the public higher education system,” writes Mr. Stange.