/pdf/convex-analysisnoer-san-nojin-zhan-nituite-5dl2rbmoyr.pdf

Convex Analysisの二,三の進展について

We investigated the differential diffusion of all of the verified true and false news stories distributed on Twitter from 2006 to 2017. The data comprise ~126,000 stories tweeted by ~3 million people more than 4.5 million times. We classified news as true or false using information from six independent fact-checking organizations that exhibited 95 to 98% agreement on the classifications. Falsehood diffused significantly farther, faster, deeper, and more broadly than the truth in all categories of information, and the effects were more pronounced for false political news than for false news about terrorism, natural disasters, science, urban legends, or financial information. We found that false news was more novel than true news, which suggests that people were more likely to share novel information. Whereas false stories inspired fear, disgust, and surprise in replies, true stories inspired anticipation, sadness, joy, and trust. Contrary to conventional wisdom, robots accelerated the spread of true and false news at the same rate, implying that false news spreads more than the truth because humans, not robots, are more likely to spread it.

The spread of true and false news online

Statistical physics has proven to be a fruitful framework to describe phenomena outside the realm of traditional physics. Recent years have witnessed an attempt by physicists to study collective phenomena emerging from the interactions of individuals as elementary units in social structures. A wide list of topics are reviewed ranging from opinion and cultural and language dynamics to crowd behavior, hierarchy formation, human dynamics, and social spreading. The connections between these problems and other, more traditional, topics of statistical physics are highlighted. Comparison of model results with empirical data from social systems are also emphasized.

Statistical physics of social dynamics

The author systematically examines one of the important issues of information — establishing the market price. He introduces the concept of «search» — where a buyer wanting to get a better price, is forced to question sellers. The article deals with various aspects of finding the necessary information.

Economics of Information

We assume that the instantaneous riskless rate reverts towards a central tendency which in turn, is changing stochastically over time. As a result, current short-term rates are not" sufficient to predict future short-term rates movements, as would be the case if the central" tendency was constant. However, since longer-maturity bond prices incorporate information" about the central tendency, longer-maturity bond yields can be used to predict future short-term" rate movements. We develop a two-factor model of the term-structure which implies that a" linear combination of any two rates can be used as a proxy for the central tendency. Based on" this central-tendency proxy, we estimate a model of the one-month rate which performs better" than models which assume the central tendency to be constant.

A Unified Theory of Underreaction, Momentum Trading and Overreaction in Asset Markets

An informational cascade occurs when it is optimal for an individual, having observed the actions of those ahead of him, to follow the behavior of the preceding individual without regard to his own information. We argue that localized conformity of behavior and the fragility of mass behaviors can be explained by informational cascades.

https://papers.ssrn.com/sol3/Delivery.cfm/SSRN_ID1405027_code2024.pdf?abstractid=1286306&mirid=1&type=2

A Theory of Fads, Fashion, Custom, and Cultural Change as Informational Cascades

/pdf/a-theory-of-fads-fashion-custom-and-cultural-change-as-3s4j8rv8xm.pdf

Learning by observing the past decisions of others can help explain some otherwise puzzling phenomena about human behavior. For example, why do people tend to converge on similar behavior? Why is mass behavior prone to error and fads? The authors argue that the theory of observational learning, and particularly of informational cascades, has much to offer economics, business strategy, political science, and the study of criminal behavior.

/pdf/learning-from-the-behavior-of-others-conformity-fads-and-2b6fi36pyc.pdf

Learning from the behavior of others : conformity, fads, and informational cascades

This paper provides an overview of the recent theoretical and empirical research on herd behavior in financial markets. It looks at what precisely is meant by herding, the causes of herd behavior, the success of existing studies in identifying the phenomenon, and the effect that herding has on financial markets. Copyright 2001, International Monetary Fund

https://link.springer.com/content/pdf/10.2307%2F3867650.pdf

Herd Behavior in Financial Markets

Policymakers often express concern that herding by financial market participants destabilizes markets and increases the fragility of the financial system. This paper provides an overview of the recent theoretical and empirical research on herd behavior in financial markets. It addresses the following questions: What precisely do we mean by herding? What could be the causes of herd behavior? What success have existing studies had in identifying such behavior? And what effect does herding have on financial markets?

https://papers.ssrn.com/sol3/Delivery.cfm/000517305.pdf?abstractid=228343&mirid=1

Sushil Bikhchandani

Papers

A Theory of Fads, Fashion, Custom, and Cultural Change as Informational Cascades

A Theory of Fads, Fashion, Custom, and Cultural Change as Informational Cascades

Learning from the behavior of others : conformity, fads, and informational cascades

Herd Behavior in Financial Markets

Herd Behavior in Financial Markets: A Review