The Role of Social Identity for Learning in Networks

该项目旨在研究社会身份对网络中社会学习动态的影响。今天，通过社交网络学习在个人、企业和政府的决策过程中发挥着关键作用。认识到社会学习对行为的重要影响，已经有大量的和不断增长的理论和实验文献，旨在了解网络学习。总之，文献表明，社会网络的结构对社会学习的动态有着深远的影响。实验研究主要集中在认知限制如何导致网络中贝叶斯学习的失败。到目前为止，还没有一篇实验性论文深入研究了社会认同在社会学习中的作用。这将是这个项目的主要贡献。我们开发了一个实验装置来研究网络中的信念形成和社会学习。我们通过两个国家之间的互联实验室实现身份群体之间的互动，使用国籍作为社会身份。参与者在网络上互动，面对任务，回答来自不同专业领域的事实问题。他们同时重复地猜测真实答案，观察他们的网络邻居在每个时期的猜测。在治疗过程中，我们改变了邻居的社会身份信息。在一系列的研究中，我们分析了不同的网络规模以及外源和内源网络结构。本文通过理论分析对实验研究进行了补充，主要贡献如下：（1）在一个简单的网络环境中验证了社会认同对网络学习的影响。特别是，我们提供了一个测试，是否个人超重的意见，从人谁分享他们的社会身份。(2)我们有助于理解社会身份如何用于社会学习，以及这如何影响结果。它是否提高了效率，特别是提高了学习的速度，还是导致了学习的扭曲和失败？例如，如果社会身份是专业知识的良好代表，歧视可以加快学习速度。(3)我们将研究不同的社会网络结构如何影响社会学习和歧视行为的动态。社会身份和学习动态之间的相互作用将在更大的网络中得到解决，这些网络允许测试各种不同的网络配置。(4)我们研究社会身份如何影响社交网络的形成，从而影响人们咨询的信息来源。特别是，我们感兴趣的是，不同的社交网络是否会出现内源性的存在或不存在的社会身份信息，以及如何影响社会福利。原则上，内源性网络的形成对社会学习是有益还是有害尚不清楚。

The proposed project aims to investigate the effect of social identity on the dynamics of social learning in networks. Learning through social networks today plays a key role in individuals’, firms’, and governments’ decision-making processes. Acknowledging the crucial impact of social learning on behaviour, there is already a large and growing theoretical and experimental literature aiming to understand learning in networks. In sum, the literature has shown that the structure of the social network has profound influence on the dynamics of social learning. Experimental studies mostly focused on how cognitive limitations can lead to failures of Bayesian learning in networks. None of the experimental papers have so far deeply studied the role of social identity for social learning. This will be the main contribution of this project.We develop an experimental setup to study belief formation and social learning in networks. We implement the interaction between identity groups by interconnecting laboratories between two countries, using nationality as social identity. Participants interact on a network and face the task to answer factual questions from various areas of expertise. They simultaneously and repeatedly guess the true answer, observing the guesses of their network neighbors in each period. Across treatments we vary information on the social identity of the neighbors. In a sequence of studies, we analyse different network sizes as well as exogenous and endogenous network structures. We complement our experimental studies with theoretical analysis.The main contributions we expect to make are the following: (1) We identify the effect of social identity on learning in networks in a clean and simple setting. In particular, we provide a test whether individuals overweight opinions from people who share their social identity. (2) We contribute to an understanding how social identity is used in social learning and how this affects the outcome. Does it improve efficiency, in particular increase the speed of learning, or does it lead to distortions and failure to learn? Discrimination can, for example, increase the speed of learning if social identity is a good proxy for expertise. (3) We will study how different social network structures influence the dynamics of social learning and discriminatory behaviour. The interplay between social identity and learning dynamics will be addressed in larger networks that allow to test a variety of different network configurations. (4) We study how social identity affects the formation of social networks and thus the source of information that people consult. In particular, we are interested in whether different social networks will emerge endogenously in the presence or absence of information on social identity and how this influences social welfare. In principle, it is not clear whether endogenous network formation is beneficial or detrimental to social learning.