For setting the pay rates/ranges of jobs where staffing hinges heavily on drawing new graduates, I find data on starting salaries for college grads in the relevant majors to be a helpful data point. Often - if your staffing practices are institution-specific, you can get that data on the college/university website or by calling the Career Placement office. But there are also some great surveys that collect and report this info.
The following data come from NACE's (National Association of Colleges and Employers) Winter 2017 Salary Survey and reflect annual salary projections by employers for Class of 2017 college graduates. In the first table, we show average starting salaries by major in alpha order.
In the second table, same starting salary data, we group the majors into their general areas.