The fourth annual U.S. News Best Global Universities rankings were produced to provide insight into how universities compare globally. Since an increasing number of students plan to enroll in universities outside of their own country, the Best Global Universities rankings – which focus specifically on schools' academic research and reputation overall and not on their separate undergraduate or graduate programs – can help those applicants accurately compare institutions around the world.
The Best Global Universities rankings also provide insight into how U.S. universities – which U.S. News has been ranking separately for more than 30 years – stand globally. All universities can benchmark themselves against schools in their own country and region, become more visible on the world stage and find top schools in other countries to consider collaborating with.
The overall Best Global Universities rankings encompass the top 1,250 institutions spread across 74 countries – up from the top 1,000 universities in 65 countries ranked last year. The first step in producing these rankings, which are powered by Clarivate Analytics InCites, involved creating a pool of 1,295 universities that was used to rank the top 1,250 schools.
To create the pool of 1,295, U.S. News first included the top 250 universities in the results of Clarivate Analytics' global reputation survey, described further below. Next, U.S. News added 1,385 institutions that had met the minimum threshold of 1,500 papers published in the 2011-2015 time frame. The last step was to remove duplicates and institutions that are not schools to reach the final 2018 ranking pool of 1,295 institutions.
As a result of these criteria, many stand-alone graduate schools, including Rockefeller University in New York and the University of California—San Francisco, were eligible to be ranked and were included in the ranking universe.
U.S. News 第四年度的“全球最佳大学排名”旨在深度比较全球范围内的大学。这个排名专门考量了大学总体的研究表现和声誉，而不局限于评估大学的本科生课程或研究生课程。鉴于计划出国留学的学生日益增多，以及这个排名对大学总体研究表现和声誉的重视，因此这个排名可以帮助申请国外高校的学生精确地对世界范围内的大学进行比较。
这项全球最佳大学综合排名囊括了74个国家(地区)的1250所大学。去年，这个排名囊括65个国家的1000所大学。这个排名得到了Clarivate Analytics InCites的数据支持。为了得出这个排名，U.S. News收集了1295所大学，在此基础上评出1250所。
为了收集1295所大学，U.S. News根据Clarivate Analytics InCites“全球声誉调查"的结果，首先选中在该调查(在下文有具体说明)中排名顶尖的250所大学。随后，U.S. News根据出版物最低数量标准(标准要求大学在2011-2015年间至少发表1500篇论文)，添加了1385所大学。最后，U.S. News减去重复的名额，移除没有入围2018年最终备选名额(1295个名额)的大学。在此基础上，选出了1295所大学。
The second step was to calculate the rankings using the 13 indicators and weights that U.S. News chose to measure global research performance. Each of the 1,250 top-ranked school's profile pages on usnews.com lists the overall global score as well as numerical ranks for the 13 indicators, allowing students to compare each school's standing in each indicator.
The indicators and their weights in the ranking formula are listed in the table below, with related indicators grouped together; an explanation of each follows.
|Global research reputation||12.50%|
|Regional research reputation||12.50%|
|Normalized citation impact||10%|
|Number of publications that are among the 10 percent most cited||12.50%|
Percentage of total publications that are
among the 10 percent most cited
|Percentage of total publications with international collaboration||5%|
Number of highly cited papers that are among the top 1
percent most cited in their respective field
Percentage of total publications that are among the top 1
percent most highly cited papers
在完成排名的第一步(即选出1295所大学)之后，U.S. News根据13个指标及权重，对大学的综合研究表现进行了评估。在1250所大学中，每一所大学在U.S. News官网(usnews.com )均有简介的页面。这个页面不仅列出了大学的综合得分，而且列出了大学在13项指标的具体排名(用数字表示)，因此有助于学生对学校的每一项指标进行比较。
Results from Clarivate Analytics' Academic Reputation Survey were used to create the two reputation indicators used in U.S. News' ranking analysis.
The survey, which aimed to create a comprehensive snapshot of academics' opinions about world universities, asked respondents to give their views of programs in the disciplines with which they were familiar. This method allowed respondents to rate universities at the field and department level, rather than at the institution level, creating a more specific and accurate measurement of a university's reputation as a whole.
To appropriately represent all regions, Clarivate Analytics took steps to overcome language bias, differing response rates and the geographic distribution of researchers. These steps included:
Sending an invitation-only survey to academics selected from Clarivate Analytics' databases of published research, based on the estimated geographic proportions of academics and researchers around the world.
Providing accessibility in seven languages.
Rebalancing the survey's final results based on the geographic distribution of researchers to overcome differing response rates.
Excluding respondents' nominations of their own institution or alma mater.
Respondents also self-declared their job role:
70 percent academic staff.
14 percent research staff.
7 percent senior institutional leaders.
4 percent graduate/postgraduate students.
5 percent other jobs and roles.
The total number of unique respondents was more than 30,000. The survey results were used in two separate ranking indicators, as follows.
U.S. News排名分析中涉及的两个声誉指标(全球声誉和地方声誉)参照了Clarivate Analytics的“学术声誉调查”。
为如实反映各个地区大学的声誉，Clarivate Analytics 采取了好几个步骤避免了语言偏倚，并让研究员的反馈率和地域分布差异化。
Global research reputation (12.5 percent): This indicator reflects the aggregation of the most recent five years of results of the Academic Reputation Survey for the best universities globally for research.
Regional research reputation (12.5 percent): This indicator reflects the aggregation of the most recent five years of results of the Academic Reputation Survey for the best universities for research in the region; regions were determined based on the United Nations definition.
The bibliometric indicators used in the U.S. News ranking analysis are based on data from Clarivate Analytics' Web of Science for the five-year period from 2011 to 2015. The Web of Science is a web-based research platform that covers more than 18,000 of the most influential and authoritative scholarly journals worldwide in the sciences, social sciences, and arts and humanities.
U.S. News 排名分析涉及的文献计量指标依据了Clarivate Analytics科学网的数据，参照了科学网2011—2015五年间的数据。科学网是一个网络研究平台数据库，它囊括了世界范围内最具影响力和原创力的1万8千多份学术期刊，内容涵盖了科学、社会科学、艺术、人文领域。
Publications (10 percent): This is a measure of the overall research productivity of a university, based on the total number of scholarly papers – reviews, articles and notes – that contain affiliations to a university and are published in high-quality, impactful journals. This indicator is closely linked to the university's size. It is also influenced by the university's discipline focus, since some disciplines, particularly medicine, publish more than others.
Books (2.5 percent): Books are an important medium of publication for scholarly research, particularly in the social sciences, arts and humanities. The use of this ranking indicator provides a useful supplement to the data on articles and better represents universities that have a focus on social sciences and arts and humanities.
Normalized citation impact (10 percent): The total number of citations per paper represents the overall impact of the research of the university and is independent of the university's size or age; the value is normalized to overcome differences in research area, the paper's publication year and publication type.
Total citations (7.5 percent): This indicator measures how influential the university has been on the global research community. It is determined by multiplying the publications ranking factor by the normalized citation impact factor. Total citations have been normalized to overcome differences in research area, publication year of the paper and publication type.
Number of publications that are among the 10 percent most cited (12.5 percent): This indicator reflects the number of papers that have been assigned as being in the top 10 percent of the most highly cited papers in the world for their respective fields. Each paper is given a percentile score that represents where it falls, in terms of citation rank, compared with similar papers – those with the same publication year, subject and document type.
Since the number of highly cited papers is dependent on the university's size, the indicator can be considered a robust indication of how much excellent research the university produces.
Percentage of total publications that are among the 10 percent most cited (10 percent): This indicator is the percentage of a university's total papers that are in the top 10 percent of the most highly cited papers in the world – per field and publication year. It is a measure of the amount of excellent research the university produces and is independent of the university's size.
International collaboration (5 percent): This indicator is the proportion of the institution's total papers that contain international co-authors divided by the proportion of internationally co-authored papers for the country that the university is in. It shows how international the research papers are compared with the country in which the institution is based. International collaborative papers are considered an indicator of quality, since only the best research will be able to attract international collaborators.
Percentage of total publications with international collaboration (5 percent): This indicator is the proportion of the institution's total papers that contain international co-authors and is another measure of quality.
3.Scientific Excellence Indicators
Number of highly cited papers that are among the top 1 percent most cited in their respective field (5 percent): This highly cited papers indicator shows the volume of papers that are classified as highly cited in the Clarivate Analytics' service known as Essential Science Indicators. Highly cited papers in ESI are the top 1 percent in each of the 22 subject areas represented in the Web of Science, per year. They are based on the most recent 10 years of publications.
Highly cited papers are considered indicators of scientific excellence and top performance and can be used to benchmark research performance against subject field baselines worldwide. This is a size-dependent measure.
Percentage of total publications that are among the top 1 percent most highly cited papers (5 percent): This percent of highly cited papers shows the number of highly cited papers for a university divided by the total number of documents it produces, represented as a percentage. It is a measure of excellence and can show what percentage of an institution's output is among the most impactful papers in the world. This is a size-independent measure.
在各自领域前1%最常被引用的论文数量(5%)。这个指标显示了在 Clarivate Analytics服务平台中被归类为最常被引用的论文的数量。Clarivate Analytics也被称为基本科学指标数据库。该数据库最常被引用的的论文就是“科学网”22个学科每年前1%最常被引用的论文。它们依据了最近十年的发表的论文的引用情况。
4.University Rankings by Region
The U.S. News Best Global Universities rankings by region show the top institutions in five regions with a large number of globally ranked schools. Those regions are Africa, Asia, Australia/New Zealand, Europe and Latin America. To determine which countries are in which region, we used the U.N. definition of geographical regions.
The methodology for the region rankings is based entirely on how a school ranked in the overall Best Global Universities rankings covering the top 1,250 schools worldwide. Universities are numerically ranked in their region based solely on their position in the overall Best Global Universities rankings.
For example, in Europe, the highest-ranked university in the overall top 1,250 rankings is the United Kingdom's University of Oxford, at No. 5 globally. This overall position also makes the school No. 1 in Europe. The second highest-ranked university in Europe is the U.K.'s University of Cambridge, which is ranked No. 7 globally, thereby making it No. 2 in Europe.
U.S. News全球最佳大学区域排名列出了五个地区的顶尖大学。各地区都有许多大学进入全球排名。这五个地区分布是非洲、亚洲、澳洲(澳大利亚、新西兰)、欧洲和拉丁美洲。为了明确各地区都有哪些国家，我们采用了联合国的地理区域鉴定。 区域排名完全根据学校在全球最佳大学综合排名中的表现来进行的。全球最佳大学综合排名囊括了世界1250所顶尖的大学。学校在地区排名中的名词用数字表示。地区名次完全根据学校在全球最佳大学综合排名中的表现来排列。 例如，欧洲在世界排名最高的大学是英国的牛津大学，位列第五位。那么，在欧洲大学排名中牛津大学也排在第一位。欧洲在世界排名第二高的大学是英国的剑桥大学，位列全球第七位，那么在欧洲大学排名中剑桥大学也排在第二位。
5.University Rankings by Country
The U.S. News Best Global Universities rankings by country show the top institutions in 42 countries with five or more schools that are globally ranked in the top 1,250.
The methodology for the country rankings is based entirely on how a school ranked in the overall Best Global Universities rankings covering the top 1,250 schools worldwide. Universities are numerically ranked in their country based on their position in the overall Best Global Universities rankings.
For example, in Canada, the highest-ranked university in the overall top 1,250 rankings is the University of Toronto, at No. 20 globally. This overall position also makes the school No. 1 in the Best Global Universities in Canada rankings. The second highest-ranked university in Canada in the overall rankings is the University of British Columbia, ranked at No. 27 globally, thereby making it No. 2 in Canada.