English to Serbo-Croat Other Mathematics & Statistics tools and machines

• SCHOOL is a vector of school characteristics, which include: average annual spending per student from 2005 to 2010; salary expenditures as a percent of all school spending in 2010; non-teaching staff salaries as a percent of all salary spending in 2010; teachers’ average years of experience in 2010; percent of teachers with a university degree in 2010; average 8th grade class size in 2011 and average class size squared (to allow for a potential quadratic relationship between class size and learning outcomes);