http://www.usnews.com/usnews/edu/gra...thod_brief.php
Please read and understand how the rankings are derived.....
The ranking methodology
Each year, U.S. News ranks graduate programs in the areas of business, education, engineering, law, and medicine. These rankings are based on two types of data:** expert opinion about program quality and statistical indicators that measure the quality of a school's faculty, research, and students. **For the rankings in all five areas, indicator and opinion data come from surveys of more than 1,000 programs and nearly 7,000 academics and other professionals conducted in the fall of 2002.
This year, we also produced new rankings of graduate programs in selected health fields and the fine arts, surveying nearly 2,000 faculty and administrators. The rankings in these fields, plus those from previous years in health-related fields, humanities, sciences, social sciences, and public affairs, are based solely on the ratings of academic experts.
**To gather the opinion data, we asked deans, program directors, and senior faculty to judge the overall academic quality of programs in their field on a scale of 1 ("marginal") to 5 ("outstanding"). **In business, education, engineering, law, and medicine, we also surveyed professionals in the field who are part of the hiring process.
The statistical indicators used in our rankings of business, education, engineering, law, and medical schools fall into two broad categories: inputs, or measures of the qualities that students and faculty bring to the educational experience; and outputs, measures of graduates' achievements that can be credited to their educational experience.
Different output measures are available for different fields, and, as a result, the indicators we use in our models vary. In business, the immediate impact of students' education can be gauged by their salaries after graduation and by how much time it takes them to find jobs. In law, we also look at how long it takes grads to land jobs, plus their bar exam passage rates. In the other fields we rank, job placement data aren't tracked as rigorously, so in our calculations we use data like–for one example–the percentage of graduates entering the field in primary-care medicine.
To arrive at a school's rank, we examined the distribution of the data for each quality indicator. Where the data deviated significantly from the normal distribution, we used standard statistical techniques to make the distribution of the values closer to that of a normal curve. We then standardized the value of these indicators about its mean. The weights applied to the indicators reflect the relative importance of the indicators, as developed in consultation with experts in each field. (Detailed information about the weights and indicators appears with the tables.) The final scores were rescaled: The highest-scoring school was assigned 100, and the other schools' scores were recalculated as a percentage of that top score. The scores were then rounded to the nearest whole number and schools placed in descending order. Every school's performance is presented relative to the other schools with which it is being compared. So a school with an overall score of 100 did not necessarily top out on every indicator; rather it accumulated the highest composite score. A school's rank reflects the number of schools that sit above it; if three schools are tied at 1, the next school will be numbered 4, not 2. Schools that are tied are listed in alphabetical order.