经济与社会科学2016melbourneinstitute.com
用进废退？工作时间对认知能力的影响
Use It Too Much and Lose It? The Effect of Working Hours on Cognitive Ability
入门 · 约 45 分钟读完前置知识：计量经济学基础、工具变量方法
导读
这篇墨尔本研究所的工作论文利用澳大利亚老年人群数据，研究每周工作时长对认知能力的影响。结论是：每周工作约 25 小时以内时，工作时长增加对认知功能有正面作用；超过 25 小时后，继续增加工时反而对认知产生负面影响，且男女之间无显著差异。
HN 关注点：是因为结论常被媒体解读为支持每周三天工作制，同时其因果推断方法（工具变量）引发了大量质疑。
HN 评论精选
这几条评论里：质疑 2 补充 2
补充概括论文核心结论（25 小时拐点），并提醒样本仅限 40 岁以上、未做年龄分层
摘要的 TL;DR：每周工作约 25 小时以内时，增加工时对认知功能有正面影响；超过 25 小时后，增加工时对认知有负面影响。男女之间无显著差异。重要细节：研究只针对 40 岁及以上人群，因此不能仅凭这篇论文对年龄组差异下结论；而且从文末表格看，样本内部也没有按年龄分层分析，只列出了三个 15 岁宽度年龄组的样本量。
Noseshine查看英文原文
The TL;DR summary from the abstract: > For working hours up to around 25 hours a week, an increase in working hours > has a positive impact on cognitive functioning. However, when working hours > exceed 25 hours per week, an increase in working hours has a negative impact > on cognition. No significant difference between women and men. Important detail: They only looked at people 40 or older, so no conclusions should be attempted based on this paper alone about differences between older and younger groups (above/below 40). Looking at their tables at the end of the paper I also didn't see any stratification by age within the sampled group, they only listed the sample size for three (15 years wide) age groups (Table II).
质疑质疑工具变量的有效性，认为因果推断不成立；并反驳三天工作制的媒体解读
这是我在经济学论文里见过的最没有说服力的工具变量之一。他们甚至没有尝试论证为什么'父母是否健在'、'领取其他公共福利'、'拥有自己的住房'、'子女数量'或'工作经验'这些变量在因果上独立于智力——这些根本不可能构成支持因果推断的有效工具变量。论文自己都承认'用于排除性约束的变量的有效性有待未来研究'。另外我也反对媒体把它包装成支持每周三天工作制的论据：即使认知表现在三天时达到峰值，由于工时被拆散以及企业雇用大量兼职者的管理开销，员工整体绩效仍可能更差。
aab0查看英文原文
This is one of the most unconvincing instruments I've ever seen in an economics paper. They don't even try to justify why variables like 'parents alive' (!), 'other public benefits' (!!), 'owning your own house' (!!!), or 'number of children' or 'work experience' (!!!!) are all causally independent of intelligence. There's no way these form a valid instrument allowing causal inference. Hey, why not throw in education or grades while you're at it, after all, "The validity of the variables used to generate exclusion restrictions needs to be investigated in future research", since that would be as valid an instrumental variable as any of the others... (I also object to the media framing this as an argument for 3-day work weeks. If cognitive performance peaked at 3-days, employee performance could still be way worse due to the few hours split up, in addition to the economic overhead for businesses of having many part-timers.)
补充提供加班损害产出和每小时 GDP 的补充资料
补充相关研究：游戏行业有一项研究比较了游戏评分与加班赶工（crunch）的关系，见 http://www.gamasutra.com/blogs/PaulTozour/20150120/234443/The_Game_Outcomes_Project_Part_4_Crunch_Makes_Games_Worse.php ；另外 OECD 有每小时工作对应的 GDP 数据：http://stats.oecd.org/Index.aspx?DataSetCode=PDB_LV
acd查看英文原文
Here is a study from the game industry where game scores are compared to coding crunch. http://www.gamasutra.com/blogs/PaulTozour/20150120/234443/The_Game_Outcomes_Project_Part_4_Crunch_Makes_Games_Worse.php There is GDP per hour worked. http://stats.oecd.org/Index.aspx?DataSetCode=PDB_LV
质疑指出可能存在反向因果/选择偏差：认知能力本身决定了工时
我没细读论文，如果这点没被控制住的话：这种关系很难控制，因为完全不工作或工作极长的人，本来可能就不如正常或略低于正常工时的人有能力。比如，如果我能找到一份工作并在更短时间内赚到足够的钱，那我大概比找不到工作或每周必须工作 65 小时以上的人更聪明——即使考虑了学历等因素。
ultramancool查看英文原文
I didn't read it in detail, so forgive me if this was accounted for, but I feel like this would be hard to control as people who are not working at all or working extremely long hours may not be as capable as those working a normal or slightly lower than normal numbers of hours to begin with. For example, if I can get a job and make enough money in a shorter number of hours, I'm probably smarter than the person who can't get or a job or the person who has to work 65+ hours a week, even if accounting for degree or similar.
历次讨论
- 2016Hacker News 讨论帖179 分 · 43 评
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