Not a scientific study

Comment on "Single children 'little emperors'" (China Daily, Jan 28)

I was shocked to read the article, especially because the study was conducted by four professors from Australia. A scientific survey is based on three factors: sample, test and results. And the sample size of 421 is far from being big enough to represent Beijing's population of 20 million.

The age distribution of the cohorts is limited to a period of eight years, four years before and four years after 1979, when the family planning policy was implemented across China. But it took years for the "little emperor" mentality to develop. Therefore, people born between 1980 and 1983 are not exactly representative of the "one-child" policy.

We also know that having only one child is often the choice of many well-off families. This becomes obvious when we compare the birth rates of the most developed and the less developed countries. Thus the basic criterion of sample composition, in the present case, is a failure both in terms of quantity (number) and quality.

The four experiments used in the study were borrowed from "economics literature". But are they the best way to study social and personal behavior? The results of the two cohorts are quite close, but the study's authors seem to find them significant. Worse, the conclusions of the survey extend to aspects which were not studied. Isn't this an apt example of "jumping to conclusions"?

Perhaps China Daily should not have published the article. But I felt relieved after reading the accompanying article by Li Xiaoping, of the Chinese Academy of Social Sciences. Li rightly points out the weaknesses in the Australian researchers' findings.

Lisa Carducci, Beijing

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(China Daily 02/05/2013 page9)