College and university rankings are rankings of institutions in higher education ordered by various combinations of various factors. Rankings have most often been conducted by magazines, newspapers, websites, governments, or academics. In addition to ranking entire institutions, organizations perform rankings of specific programs, departments, and schools. Various rankings consider combinations of measures of wealth, research excellence and/or influence, selectivity, student options, eventual success, demographics, and other criteria. There are no known college rankings of student academic quality. Some rankings evaluate institutions within a single country, while others assess institutions worldwide. The subject has produced much debate about rankings' usefulness and accuracy. The expanding diversity in rating methodologies and accompanying criticisms of each indicate the lack of consensus in the field.