经济与社会科学2025arxiv.org
四分之一美国培养的科学家最终离开
A quarter of US-trained scientists eventually leave
入门 · 约 30 分钟读完前置知识：博士培养体系基本概念、专利引用计量常识
导读
这篇论文研究美国培养的科学人才（博士毕业生）的流失情况，发现约四分之一最终离开美国。论文追踪了毕业生的去向及其对科学产出的影响：迁移后美国占全球专利引用这些毕业生科研成果的比例从 70% 降至 50%，但仍达到目的地国家份额的五倍，说明美国仍从这一人才流动中获益。
HN 关注点：人才流失的规模与原因：是学术岗位稀缺、中国的人才计划，还是移民政策与排外氛围所致，讨论焦点在于这对美国科研竞争力意味着什么。
HN 评论精选
这几条评论里：质疑 1 补充 2 亲历 1
质疑认为人才流向中国是中国系统性人才计划的刻意结果
“40% 去了中国”——这不是巧合，而是计划。中国向其公民提供巨额“资助”，让他们来美国接受教育、在大厂或科研领域工作，然后把学到的一切带回国。
cavisne查看英文原文
“40% move to China” This is the plan not a coincidence. China pays huge “grants” to their citizens to come to the US, get educated, work in big tech/science, then bring it all home.
补充结构性问题是学术岗位远少于博士培养数量，流失在所难免，但美国仍是净受益方
我的理解是科研存在双重问题：维持现有教授研究所需的学生数量远多于可提供的初级教职岗位，结果大多数博士必须离开（美国）学术界，因为根本没有职位。事实上有科学家抱怨大学有义务帮学生毕业后在工业界找工作。既然如此，教授们去哪找愿意留下来的学生？很多学生最终成为有移民意愿的人，毕业后难以立足、选择离开也就不奇怪了。另外摘要指出美国仍从中获益很大：迁移后美国占全球专利引用的比例从 70% 降到 50%，但仍是目的地国家份额的五倍。
msteffen查看英文原文
My understanding is that scientific research has a dual problem, where the number of students needed to carry out existing professors' research is much larger than the number of junior faculty positions generally available. The result being that most trained PhDs must leave (US) academia because there are no jobs for them. In fact, I've heard scientists complain that universities owe it to students to provide more help finding a job in industry after they graduate. Given all that, where are professors supposed to find and hire students who don't want to stay in academia themselves? I think a lot of these students wind up being aspiring immigrants, and I'm not surprised that a lot of them would also have a hard time finding a place for themselves after graduating and that many of them would leave. Also, the abstract seems to argue that that US still benefits greatly from this arrangement: "though the US share of global patent citations to graduates' science drops from 70% to 50% after migrating, it remains five times larger than the destination country share."
亲历亲历视角：排外氛围和政策正在劝退留学生，造成代际性的人才流失
我想知道这有多大的代际影响。我儿子在常春藤读博，他说外国学生是学校最赚钱的生源（每个外国学生带来的学费远高于本国学生）。这些学费通常由父母支付——他们是二十多年前怀揣“美国教育梦”成长起来的一代人。但孩子们在求学过程中发现在这里生活和学习越来越不友好，于是想“回家”。排外言论和政策正在产生效果，他完全不认为这是好事。我的几个孩子也考虑出国留学。夹在他们和祖辈之间很奇怪——祖辈们被 Fox News 的内容洗脑，还以为这对孙辈有好处。
travisgriggs查看英文原文
I wonder how much generational impacts there are here. My son is a PhD student at an ivy. The most lucrative tuition source for the university is foreign students (as in, they bring in far more tuition dollars for each foreign student than they do native). He has also observed that the payers of these tuitions are usually the parents, who tend to be people who rose through the ideal of "the dream of american education" that is now 20+ years old. As the students (children) go through the programs, they are finding it increasingly more hostile to live and study here. So they end up wanting to "go back home". The Xenophobic rhetoric, as well as the policies, are having an effect. He does not see this as a good thing at all. Multiple of my children have considered moving abroad to study. It's weird to sit between them and their frustration of the system, and their grandparents (our parents) who seem to think that the crap they're embibing off of fox news, all so that advertisers can target/fleece the older generation, will actually lead to good for their grandchildren.
补充从全球视角看人才输出是正和博弈
一个更积极的视角是：美国每输出一名博士，都是在把世界其他地区的科学水平拉高。
slwvx查看英文原文
A more positive-sum view is that the US is bringing the rest of the world up in science every time it exports a PhD.
历次讨论
- 2025Hacker News 讨论帖154 分 · 172 评
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