Tuesday, March 22, 2022

China has overtaken the US when it comes to the highest-impact research. Really?

Very doubtful! Sure, Chinese scientists are as good or sometimes better than any other scientists. However, I suspect the metric and/or the scope of the study (e.g. which areas of science) etc. is flawed.

You wonder almost why the Royal Society of Chemistry publishes such an article without any reservation and with such a title!

The Scientometrics journal, in which this study was published, has an impact factor of 3238. That is very high and indicates little impact or does it meant the journal is obscure?

Citations count by itself can be a very flawed and primitive metric! What if Chinese scientists preferably (e.g. politeness, courtesy) or for other reasons cite other Chinese colleagues more often than other scientists? What if the Communist Party of China ordered or expects such preferential citations?
It appears the citations itself where not analyzed in terms of who cites who (e.g. self citations or was the citation actually relevant) etc.

When you look at the chart below (Fig. 2 of the study), you wonder what caused the sudden and sharp rise of the China curve between 2015-2019.

"China has surpassed the US to become the world leader in producing the highest-impact scientific research, according to new analysis based on the Web of Science (WoS) database and published in the journal Scientometrics. Experts argue, however, that China’s greater publication output and citations doesn’t necessarily mean that it is generating more high-quality science than the US and other nations.

The new study, carried out by a three-person research team from the US, Europe and China, shows that Chinese research ranked as high as or higher than US work in the top 1% of scientific studies in 2019, after passing the EU by this measure in 2015. ..."

From the abstract:
"The top-1% most-highly-cited articles are watched closely as the vanguards of the sciences. [????] Using Web of Science data, one can find that China had overtaken the USA in the relative participation in the top-1% (PP-top1%) in 2019, after outcompeting the EU on this indicator in 2015. However, this finding contrasts with repeated reports of Western agencies that the quality of China’s output in science is lagging other advanced nations, even as it has caught up in numbers of articles. The difference between the results presented here and the previous results depends mainly upon field normalizations, which classify source journals by discipline. Average citation rates of these subsets are commonly used as a baseline so that one can compare among disciplines. However, the expected value of the top-1% of a sample of N papers is N / 100, ceteris paribus. Using the average citation rates as expected values, errors are introduced by (1) using the mean of highly skewed distributions and (2) a specious precision in the delineations of the subsets. Classifications can be used for the decomposition, but not for the normalization. When the data is thus decomposed, the USA ranks ahead of China in biomedical fields such as virology.[I bet there are plenty of other, very relevant fields of research where the USA ranks higher e.g. AI & machine learning] Although the number of papers is smaller, China outperforms the US in the field of Business and Finance (in the Social Sciences Citation Index; p < .05). [That result is almost laughable]Using percentile ranks, subsets other than indexing-based classifications can be tested for the statistical significance of differences among them."


China has overtaken the US when it comes to the highest-impact research | News | Chemistry World (behind paywall) 1.67% of papers by Chinese researchers were among the top 1% of the most highly cited articles in 2019, versus 1.62% of those with US authors




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