This paper investigates opinion dynamics and social influence in directed communication networks. We study the properties of a generalized boundedly rational model of opinion formation in which individuals aggregate the information they receive by using weights that are a function of their neighbors’ indegree. We then present an experiment designed to test the predictions of the model. We find that both Bayesian updating and boundedly rational updating à la DeMarzo et al. (2003) are rejected by the data. Consistent with our theoretical predictions, the social influence of an agent is positively and significantly affected by the number of individuals she listens to. When forming their opinions, agents do take into account the structure of the communication network, although in a sub-optimal way.
|Keywords:||Social Networks, Learning, Social In uence, Bounded Rationality|
|JEL:||D85 D83 A14 L14 Z13|
|By:||Yuichi Yamamoto (Department of Economics, University of Pennsylvania)|
We investigate whether two players in a long-run relationship can maintain cooperation when the details of the underlying game are unknown. Specifically, we consider a new class of repeated games with private monitoring, where an unobservable state of the world influences the payoff functions and/or the monitoring structure. Each player privately learns the state over time but cannot observe what the opponent learned. We show that there are robust equilibria in which players eventually obtain payoffs as if the true state were common knowledge and players played a “belief-free” equilibrium. We also provide explicit equilibrium constructions in various economic examples
|Keywords:||repeated game, private monitoring, incomplete information, belief-free equilibrium, ex-post equilibrium, individual learning|
A learning theory is proposed which models the influence of experience on end behavior in finite Prisoner’s Dilemma supergames. The theory is compared with experimental results. In the experiment 35 subjects participated in 25 Prisoner’s Dilemma supergames of ten periods each against anonymous opponents, changing from supergame to supergame. The typical behavior of experienced subjects involves cooperation until shortly before the end of the supergame. The theory explains shifts in the intended deviation period. On the basis of parameter estimates for each subject derived from the first 20 supergames, successful predictions could be obtained for the last five supergames.
notes by yinung
聽過一種說法: 大廠在向供應商採購時, 會故意隔幾年向另向一個競爭廠下大量訂單, 以讓這些廠商形成具有經濟規模的競爭者… 這一篇看起來好像在講這個故事
In many important high-technology markets, including software development, data processing, communications, aeronautics, and defense, suppliers learn through experience how to provide better service at lower cost. This paper examines how a buyer designs dynamic competition among rival suppliers to exploit learning economies while minimizing the costs of becoming locked in to one producer. Strategies for controlling dynamic competition include the handicapping of more efficient suppliers in procurement competitions, the protection and allocation of intellectual property, and the sharing of information among rival suppliers.
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Items Citing this Item
2 item(s) in JSTOR cite this item
George Loewenstein & Daylian M. Cain & Sunita Sah, (2011) “The Limits of Transparency: Pitfalls and Potential of Disclosing Conflicts of Interest,"
American Economic Review, vol. 101(3), pages 423-28, May. [link to AER]
Noted by Yi-Nung
這篇提及到 Can and Moore (2005, 2011) 的實驗, 有關利益衝突與揭露 (disclosure of conflicts);
centipede game (揭露/未揭露 first mover 的 payoff)
理專/Broker 揭露/未揭露 commission
Ultimatum game 改成 部份捐款給慈善機構 (或 as a public good), 是否會緩和 fairness 的要求
主要結論: more information, in general, is not very effective in improving decisions…. that disclosure does not replace more effective measures, such as working harder to eliminate conflicts of interest in the first place.
p.424: … the introduction of a subsidy or fine can undermine nonmaterial motives, disclosing a conflict of interest can likewise undermine the advisor’s motivation to adhere to professional standards. … Experimental research suggests that … people feel “licensed" to act immorally in subsequent interactions. Disclosure also introduces a possible rationalization for unethical behavior…"expect" bias.
research on judgment suggests that advisees are likely to “anchor" on the advice they receive and then adjust insufficiently, even though they know the advice may be biased (Tversky and Kahnemen, 1974) (先說先嬴…)
…disclosure can lead to an increase rather than a decrease in trust if the disclosure is interpreted as a sign of honesty or if the fact that the advisor is receiving payments is interpreted as in indication of professional standing.
(p.242) In the absence of disclosure,…, a patient’s rejection of participation in a drug trial would likely be attributed to risk aversion… The same rejection,… might be attributed to the patient’s distrust of the doctor
We review evidence from our published and ongoing research that disclosing conflicts of interest has unintended consequences, helping conflicted advisors and harming their advisees: With disclosure, advisors feel comfortable giving more biased advice, but advisees do not properly adjust for this and generally fail to sufficiently discount biased advice. Disclosure also increases pressure on advisees to comply with advice; following disclosure, advisees feel more uncomfortable in turning down advice (e.g., it signals distrust of the advisor’s motives). Finally, we examine the effectiveness of policy interventions aimed at reducing these unintended consequences and discuss how to realize potential benefits of disclosure.