Hahn Matthew W, Bentley R Alexander
Department of Biology, Duke University, Box 90338, Durham, NC 27708, USA.
Proc Biol Sci. 2003 Aug 7;270 Suppl 1(Suppl 1):S120-3. doi: 10.1098/rsbl.2003.0045.
In the social sciences, there is currently no consensus on the mechanism by which cultural elements come and go in human society. For elements that are value-neutral, an appropriate null model may be one of random copying between individuals in the population. We show that the frequency distributions of baby names used in the United States in each decade of the twentieth century, for both males and females, obey a power law that is maintained over 100 years even though the population is growing, names are being introduced and lost every decade and large changes in the frequencies of specific names are common. We show that these distributions are satisfactorily explained by a simple process in which individuals randomly copy names from each other, a process that is analogous to the infinite-allele model of population genetics with random genetic drift. By its simplicity, this model provides a powerful null hypothesis for cultural change. It further explains why a few elements inevitably become highly popular, even if they have no intrinsic superiority over alternatives. Random copying could potentially explain power law distributions in other cultural realms, including the links on the World Wide Web.
在社会科学领域，目前对于文化元素在人类社会中兴衰的机制尚无共识。对于价值中立的元素，一个合适的零模型可能是群体中个体之间的随机复制。我们发现，20世纪美国每十年使用的男女婴儿名字的频率分布均遵循幂律，即使人口在增长、名字每十年都有增减且特定名字的频率有大幅变化，这种幂律仍维持了100多年。我们表明，这些分布可以通过一个简单过程得到令人满意的解释，即个体之间随机相互复制名字，这一过程类似于具有随机遗传漂变的群体遗传学无限等位基因模型。因其简单性，该模型为文化变迁提供了一个有力的零假设。它还进一步解释了为什么即使某些元素相对于其他元素没有内在优势，少数元素也不可避免地会变得非常流行。随机复制有可能解释其他文化领域的幂律分布，包括万维网上的链接。
