The concept of Dunbar number is not commonly used or even unknown, but many social network engineers may know it, because the superposition of Dunbar number and six-degree theory is the core idea of many social networks.
Robin Dunbar was born on June 28th, 1947. Dunbar's father is an engineer. Dunbar studied at Magdalene College in Blackley. ) in Brackley, Oxford, England. This school was established in the center of 1480 Oxford, accommodating 700 students aged 7- 18. It is a famous co-educational school in Britain. Then he went to Magdalen College in Oxford University. According to China people's understanding, it's a bit like reading the middle school attached to Peking University and then entering Peking University. In fact, these two schools are not directly affiliated. They are more like attending Beijing No.4 Middle School and entering Peking University, but they are both located in Beijing.
Dunbar completed his bachelor of arts degree in psychology and philosophy in 1969. Then he entered the Department of Psychology of Bristol University, 1974 to complete his doctorate.
Dunbar's academic and research career includes Bristol University, Cambridge University 1977 to 1982, University College London 1987 to 1994. From 65438 to 0994, Dunbar became a professor of evolutionary psychology at the University of Liverpool. Since 2007, he has been the director of the Institute of Cognitive and Evolutionary Anthropology at Oxford University. He is a famous anthropologist and evolutionary psychologist. His famous works include How Many Friends Do We Need, gfd, Gossip and the Evolution of Language.
Dunbar number is also called 150 law. According to the intelligence and social network of apes, this law infers that the number of people whose intelligence will make human beings have a stable social network is 148, and the rounding is about 150. The law points out that the size of human neocortex is limited, and the cognitive ability provided can only make a person maintain a stable interpersonal relationship with about 150 people, which is the number of friends that people have and have personal relationships with themselves. In other words, people may have 150 friends, or even more "friends" of social networking sites, but in real life they only maintain a "small circle" of about 150 people. In this theory, "inner circle" friends refer to people who contact at least once a year.
Dunbar number experiment has actually been going on for many years. We observe primates first, then actually investigate human beings and send "postcards" (China people don't have this habit, and foreigners keep in touch by sending postcards to relatives and friends). Finally, we found that the number 148 accords with the habit of 80% people. Of course, if the accuracy is improved to 95%, it is 65438+.
Of course, all coins have tails, not to mention the so-called law. Other scholars question Dunbar number. Philip Lieberman, a famous scholar, was born in 1934, and is a cognitive scientist at Brown University in Providence, Rhode Island, USA.
Philip Lieberman believes that if we study primate populations, we should look for the data of ancient humans as direct evidence. He believes that 1.50 million years ago, due to the lack of food, the population that human beings could usually complete production and writing was usually between 30 and 50, but it was impossible to reach 1.50.
H Russell Bernard, an American scholar, was born in new york, USA on June 1940. He is a professor at the University of Arizona and a cultural anthropologist who studies technology and social change, language death and social network analysis. Peter Kilworth, a British scholar, was born on March 27th, 1946, and died on October 28th, 2008. He is an Englishman, a professor at Cambridge University, studying oceanography and social networks. By studying the social behavior of Americans, they think that the average size of social groups in interpersonal relationships is 290, almost twice the number of Dunbar. The median value is 2,365,438+0, but it is still much larger than Dunbar's rounded number of 65,438+050. Their number is called Bernard Kilworth's number, but it is not as famous as Dunbar's number, but it is a study of modern human beings, of course, Americans, not the whole world.
Xue Zhi believes that Philip Lieberman mentioned the food problem, that is, when there is enough food, there will be more social interaction. In fact, most of our social activities in China are "eating". Up to now, I have consulted seven times a day at most, but I often get a reward in the end, called "Why don't we have a meal?" I have been refusing to eat with the mentality of losing weight, but it seems that even if I throw this idea out, I will get "we have to eat anyway" immediately, so I have to wait for the next wave to come to the door and "hide from food". In fact, the friends we often talk about are often inseparable from eating and drinking, and even account for a large proportion of our social total. As for the Dunbar 150 figure, I don't think it is appropriate to study China people, but Bernard Kilworth's figure seems to be relatively large, which has a social concept for China people. My WeChat friends are about 1000 people, and there are about 200 people talking every day, including about 150 people with social relations and about 50 people with close friends and family, not counting various groups and not counting holiday wishes. If it exceeds this number, there are special circumstances, such as the project application period, but to reach an average of 290 people a day, first of all, my mobile phone will be dead after several uses, and secondly, it will not be a friend, nor will it be as "social" as I thought. From this point of view, I still agree that the number 150 is more appropriate as the community scope of my thesis, but it does not conform to the law of 150, but I agree with Bernard Kilworth more, but excluding family and friends, I think 150 is more appropriate. So I will still use "Dunbar number" as the basis of studying social networks in my thesis.