Different rating agencies, in the US, follow different methods for providing ratings. They focus on variety of areas a college while assessing. Standardized test scores of a college are considered by three raters such as US News & World Report, Washington Monthly, and Kiplinger.
Graduation rates and or student retention rates are measured by four raters. Prestigious awards or scholarships to students/faculty/alumni are also considered by three raters. However, most of the raters consider only certain segment, achievement, performance of a college.