看得見的一隻手---新聞媒體之影響

Abstract

本計畫將研究由新聞媒體所提供之”公開”訊息對只有得到部分訊息的消費者之決策有何影響. 本文將建立一部不對稱訊息賽局, 在此賽局中每個個體僅知道部分（一個 dimension）的事實,而且將倚賴新聞媒體提供由關於其他人的訊息.本文將首先證明由媒體所提供的公開訊息將形成一第二層次信念的common knowledge.然後以此賽局之結果為基礎, 進一步分析新聞媒體如何策略性決定新聞偏差的程度. 我們將可以此模型研究重要議題如新聞偏差及媒體競爭的影響,更可進一步分析政府補貼政策之影響. 最後,我們將以此模型之架構, 應用到兩個市場：選舉及股票市場.

This project will investigate the impacts of news media as a \"public\" information provider on the decision making processes of partially informed consumers. We will construct an asymmetric information game, where each agent knows only part (one dimension) of the true state and will rely on news media to provide information about other dimensions. We will first demonstrate that the public information provided by news media will create a \"common knowledge\" on the agents` second order beliefs. After characterizing the impacts of this common knowledge in a general incomplete information game, we then examine how a news firm determines the content of news in a signaling framework. This enables us to study the issues of slanting (or news bias) and the competitive effect on the degree of slanting. Finally, we will extend this general model by considering two specific games: election and stock markets