nature

引用自己論文的問題...

Nature 上點出來期刊論文裡自我引用的問題 (這邊的自我引用包括了合作過的人)：「Hundreds of extreme self-citing scientists revealed in new database」。

開頭舉了一個極端的例子，Vaidyanathan 的自我引用比率高達 94%，而學界的中位數是 12.7%，感覺是有某種制度造成的行為？

Vaidyanathan, a computer scientist at the Vel Tech R&D Institute of Technology, a privately run institute, is an extreme example: he has received 94% of his citations from himself or his co-authors up to 2017, according to a study in PLoS Biology this month. He is not alone. The data set, which lists around 100,000 researchers, shows that at least 250 scientists have amassed more than 50% of their citations from themselves or their co-authors, while the median self-citation rate is 12.7%.

會想要提是因為想到當年 Google 的經典演算法 PageRank，就是在處理這個問題... 把 paper 換成 webpage 而已。

用人力就可以達到離心機的效果...

看到「This Human-Powered Paper Centrifuge Is Pure Genius」這個設計真的很巧妙... 全文刊登在 nature biomedical engineering 上：「Hand-powered ultralow-cost paper centrifuge」。

起源來自於小時候的玩具 (我也有印象，但忘記中文叫什麼了...)：

Here, we report an ultralow-cost (20 cents), lightweight (2 g), human-powered paper centrifuge (which we name ‘paperfuge’) designed on the basis of a theoretical model inspired by the fundamental mechanics of an ancient whirligig (or buzzer toy; 3,300 BC).

研究後發現離心速度可以到 125000rpm：

The paperfuge achieves speeds of 125,000 r.p.m. (and equivalent centrifugal forces of 30,000 g), with theoretical limits predicting 1,000,000 r.p.m.

對於無法買昂貴醫療器材的地區，這樣就有簡單但又頗有效的離心機做檢驗...

超過一半的心理研究都無法重製結果

應該是前陣子被 Nuzzel 推薦 2015 八月的老新聞，這個研究在 Nature 上發表：「Over half of psychology studies fail reproducibility test」。

這個研究重複了 98 篇原創研究來重新實驗：

In the biggest project of its kind, Brian Nosek, a social psychologist and head of the Center for Open Science in Charlottesville, Virginia, and 269 co-authors repeated work reported in 98 original papers from three psychology journals, to see if they independently came up with the same results.

結果在 100 次的實驗 (其中有 2 個是重複的) 發現只有 39 個實驗結果被重製出來：

According to the replicators' qualitative assessments, as previously reported by Nature, only 39 of the 100 replication attempts were successful. (There were 100 completed replication attempts on the 98 papers, as in two cases replication efforts were duplicated by separate teams.)

這成功率其實頗低，如果實驗無法被重製，就不能算科學研究...