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社交网络中的影响与相关性

Influence and Correlation in Social Networks
课程网址: http://videolectures.net/mlg08_mahdian_icsn/  
主讲教师: Mohammad Mahdian
开课单位: 雅虎公司
开课时间: 2008-08-25
课程语种: 英语
中文简介:
在许多在线社交系统中,用户之间的社交关系在决定用户行为方面起着重要作用。这种情况的一种方式是通过社会影响,即用户的行为可以诱导他/她的朋友以类似方式行事的现象。在存在社会影响的系统中,思想,行为模式或新技术可以像流行病一样通过网络传播。因此,从分析(例如,预测系统的未来)和设计(例如,设计病毒营销策略)的观点来看,识别和理解社会影响是极大的兴趣。    在本次演讲中,我将概述社交网络中的扩散模型,然后讨论识别数据中社会影响的问题。这通常是一项困难的任务,因为还存在许多其他因素,例如同质或未观察到的混杂变量,这些因素可以引起社交网络中朋友的行为之间的统计相关性。因此,区分影响与其他因素基本上是区分相关性与因果关系的问题,因果关系是一个众所周知的难题。尽管如此,我将展示如何在可观察行动的时间戳的环境中,我们可以设计简单的统计测试,以区分社会影响模型和复制上述社会相关来源的模型。我将描绘其中一个测试的理论证明的证明,并呈现来自Flickr的随机生成的数据和真实标记数据的模拟结果。结果表明,尽管该系统的标记行为存在显着的社会相关性,但这种相关性不能归因于社会影响。
课程简介: In many online social systems, social ties between users play an important role in dictating users' behavior. One of the ways this can happen is through social influence, the phenomenon that the actions of a user can induce his/her friends to behave in a similar way. In systems where social influence exists, ideas, modes of behavior, or new technologies can diffuse through the network like an epidemic. Therefore, identifying and understanding social influence is of tremendous interest from both an analysis (e.g., predicting the future of the system) and a design (e.g., designing viral marketing strategies) point of view. In this talk, I will give a general overview of models for diffusion in social network, and then discuss the problem of identifying social influence in the data. This is a difficult task in general, since there are many other factors such as homophily or unobserved confounding variables that can induce statistical correlation between the actions of friends in a social network. Thus, distinguishing influence from those other factors is essentially the problem of distinguishing correlation from causality, a notoriously hard problem. Despite this, I will show how in an environment where the time stamp of the actions are observable, we can design simple statistical tests that distinguish between models of social influence and those that replicate the aforementioned sources of social correlation. I will sketch the proof of a theoretical justification of one of the tests, and present simulation results on randomly generated data and real tagging data from Flickr. The results exhibit that while there is significant social correlation in tagging behavior on this system, this correlation cannot be attributed to social influence.
关 键 词: 在线社交系统; 扩散模型; 相关性
课程来源: 视频讲座网
最后编审: 2020-06-29:cxin
阅读次数: 73