内容正文:
全国I卷D篇阅读
本文是一篇科学研究报道,文体为学术论文。文章结构分为三个部分。第一部分介绍了“群体智慧”效应的由来和原理。第二部分介绍了研究者的新实验和发现,即将群体进一步分为小组进行讨论,可以提高群体智慧效应的准确性。第三部分介绍了研究者对小组讨论的进一步研究,发现小组成员的讨论和推理可以减少误差,最后指出了这些研究的重要意义。
On March 7, 1907, the English statistician Francis Galton published a paper which illustrated what has come to be known as the “wisdom of crowds” effect. The experiment of estimation he conducted showed that in some cases, the average of a large number of independent estimates could be quite accurate.This effect capitalizes on the fact that when people make errors, those errors aren’t always the same. Some people will tend to overestimate, and come to underestimate. When enough of these errors are averaged together, they cancel each other out, resulting in a more accurate estimate. If people are similar and tend to make the same errors, then their errors won’t cancel each other out. In more technical terms, the wisdom of crowds requires that people’s estimates be independent. If for whatever reasons, people’s errors become correlated or dependent, the accuracy of the estimate will go down. But a new study led by Joaquin Navajas offered an interesting twist (转折) on this classic phenomenon. The key finding of the study was that when crowds were further divided into smaller groups that were allowed to have a discussion, the averages from these groups were more accurate than those from an equal number of independent individuals. For instance, the average obtained from the estimates of four discussion groups of five was significantly more accurate than the average obtained from 20 independent individuals.
In a follow-up study with 100 university students, the researchers tried to get a better sense of what the group members actually did in their discussion. Did they tend to go with those most confident about their estimates? Did they follow those least willing to change their minds? This happened some of the time, but it wasn’t the dominant response. Most frequently, the groups reported that they “shared