2018US News 世界大学学科排名方法介绍

　　U.S. News 第四年度的“全球最佳大学排名”不仅列出了世界综合实力顶尖的1250所大学，也评出了22个学科的大学排名。下面留学群向大家介绍U.S. News2018学科排名情况，供大家选校参考。

　　In addition to rankings of the world's top 1,250 universities overall and by region and country, the fourth annual U.S. News Best Global Universities rankings include an examination of the leaders in key academic subject areas. U.S. News used a separate methodology to publish the top global universities in 22 subject areas. The subject rankings are powered by Clarivate Analytics InCites. Clarivate provided the data and metrics used in the rankings, and the bibliometric data were based on the Web of Science.

　　These subject-specific rankings – which are not of academic majors, departments or specific schools at universities, such as business or medical schools – are based on academic research performance in those subjects. U.S. News has used various bibliometric measures, including publications and citations, as well as indicators for global and regional reputation in each specific subject.

　　In many cases, an institution that had a strong focus on a certain subject was ranked in that subject but was excluded from the overall Best Global Universities rankings encompassing the top 1,250 universities worldwide. In total, 125 universities were included in the subject rankings but not in the overall top 1,250 ranked universities. Five countries – Peru, Ghana, Indonesia, Malawi and Vietnam – were represented in the subject rankings but not among the 74 countries in the overall rankings.

　　U.S. News 第四年度的“全球最佳大学排名”列出了世界综合实力顶尖的1250所大学，也根据地区、国别对它们进行了排名。除此以外，第四年度的“全球最佳大学排名”还根据核心学科领域的评估，列出了世界大学学科排名。U.S. News采用单独的排名方法，评出并公布了22个学科领域的全球顶尖大学。这个学科排名得到了Clarivate Analytics的支持。Clarivate Analytics为排名提供了数据和参数。排名涉及的文献计量数据来源于科学网。

　　学科排名不是专业排名，也不是院系(比如商学院、医学院)排名，它依据的是大学在相关学科上的研究表现。U.S. News 采用了各种文献计量指标，这其中包括出版物、论文引用数。此外，也参照了大学的每个学科在全球及地区的声誉。

　　在多数情况下，偏科的大学根据其所偏的学科接受排名，但不出现在全球最佳大学综合排名中。全球最佳大学综合排名列出了世界范围内的1250所顶尖大学。本次学科排名有125所大学没有出现在全球最佳大学综合排名中。秘鲁、加纳、印度尼西亚、马拉维和越南这五个国家进入了学科排名，但没有出现在综合排名中。综合排名囊括了74个国家。

　　Ranking Indicators

　　The bibliometric indicators are based on data from the Web of Science for the five-year period from 2011-2015. 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.

　　The 22 subject fields used in the analysis came from subject schema in Clarivate Analytics InCites, which uses the content and citation indicators from the Web of Science. Publications are limited to those published between 2011 and 2015. However, the citations to those papers come from all publications, including the most recent data available. For the 2018 rankings, this cutoff date was May 30, 2017. It is necessary to use a slightly older window of publication to allow for citations to accumulate and provide statistically relevant results.

　　排名指标

　　文献计量指标基于科学网过去五年(2011-2015)的数据。科学网是一个以网络为基础的研究平台，它涵盖了世界范围内的1万8千多种最具影响力和原创力的学术期刊，内容涉及科学、社会科学、艺术、人文等领域。

　　本次学科排名涉及的22个学科依据了Clarivate Analytics InCites对学科的划分，后者又采用了科学网的内容和引证指标。出版物的出版年份局限在2011-2015年，但是针对这些出版物的引用则来源于所有出版物，包括最新获取的数据。本次2018年学科排名的截止日期为2017年5月30日。有必要使用稍早一些的出版窗口，以利于引用量累积，提供统计学意义上的相关结果。

　　The first step in producing the subject rankings was to create the total universe of schools that could be ranked in each field. Depending on the subject, the number of universities ranked ranged from a low of 206 for immunology to a high of 1,011 in chemistry – see the Total number of universities ranked column in the table below.

　　The size of the ranking pool in each of the 22 subject areas – except in two cases, microbiology and space science – was determined by the number of universities that had a published paper count of 250 or more in the 2011-2015 time period in the subject area. In microbiology and space science, the paper threshold was 150 and 200 papers, respectively, for the 2011-2015 time period.

　　U.S. News studied how many papers each university had published in each of the 22 subject areas and determined that the rankings could be extended in some areas, since many universities had published far more than 500 papers in the 2011-2015 period.

　　为了得出这份学科排名，第一步要做的就是找到各学科所有能进入排名的大学。根据学科的不同，进入排名的大学数量也不同。其中，免疫学只有206所大学进入排名，化学进入排名的大学则高达1011所(详情参见下表数据)。

　　在学科排名涉及的22个学科中，除了微生物学和空间科学，其余学科进入排名的大学数量均由2011-2015年间学科内发表论文数量达到要求(不低于250篇)的大学数量决定。对于微生物学和空间科学，它们在2011-2015年间发表论文最低数量要求分别是150和200。

　　U.S. News研究了每所大学在22个学科上发表论文的情况。鉴于2011-2015年间许多大学发表论文远超过了500篇，因此U.S. News也会增加部分学科进入排名的大学数量。

　　For the 2018 rankings, U.S. News worked with Clarivate Analytics' bibliometric experts to increase the number of ranked universities in four fields. The number of ranked universities published in chemistry, clinical medicine, engineering and physics increased from 400 to 600. The number of ranked schools published in the other 18 fields remained the same as last year. This meant that 6,800 universities were ranked in 22 subjects in the 2018 rankings, which is a 13.3 percent increase from the 6,000 ranked last year.

　　Many universities appear in more than one subject ranking. For example, 14 universities appear in all 22 subject rankings, 19 appear in 21 subject rankings and 18 appear in 20 subject rankings.

　　For the 2018 edition, four fields each list 600 ranked universities, four each list 400 schools and 14 fields each list 200 institutions.

　　U.S. News 同Clarivate Analytics的文献计量专家合作，在2018年学科排名中增加了四个学科的大学排名数量。这四个学科分别是化学、临床医学、工程和物理学，它们进入排名的大学从去年四百所增加到了六百所。除了这四个学科，其余18个学科进入排名的大学数量和去年一样，保持不变。也就是说，2018年学科排名(22个学科)共有6千8百所大学进入排名。同去年的6千所相比，增加了13.3%。

　　许多大学出现在多个学科的排名。例如，有14所大学全部进入了22个学科排名，19所大学进入了21个学科排名，18所大学进入了20个学科排名。

　　在2018年学科排名中，列出600所大学的有四个学科，列出400所大学的有四个学科，其余14个学科均列出了200所大学。

　　The table below shows the number of universities that published more than 250 papers and those that published more than 500 papers in each subject area from 2011 to 2015; the total number of universities ranked in each subject; and the number of schools U.S. News published rankings for in each subject area.

　　下表显示了2011-2015年发表论文 >250 的大学数量、2011-2015年发表论文>500 的大学数量、各学科进入排名的大学数量，以及U.S. News公布排名的大学数量。

　　以上内容由留学群独家翻译，版权归留学群所有，未经留学群授权许可，任何公司任何人不得复制和转载，违者必追究法律责任!