UCLA

This dissertation studies three challenges that modern democracies face: the representation of ethnic minorities, media bias, and political disinformation on social media. The first chapter analyzes the representation of ethnic minorities in dictatorships and democracies. There is a widely held belief that minorities benefit from democracy. However, I find that, on average, when the largest ethnic group in a society exceeds half of the population, ethnic minorities are treated better in autocracies and full democracies than in semi-democratic countries. The intuition is that under autocracy a leader needs little popular support, and therefore a coalition of several minorities can rule. By contrast, in a semi-democracy, the leader needs the support of more people, so a coalition of small ethnic groups is insufficient; the largest group is enough, and no other groups are necessary. Finally, holding power in highly democratic countries requires broad support, and most ethnic groups get benefits. I use a modified Baron-Ferejohn bargaining game to model resource- and power-sharing among the ethnic groups. In this game, each ethnic group is a unitary actor. I analyze the scenario when there is one large and several small ethnic groups. At each stage of the game, a randomly selected player proposes the division of a resource. If a fixed share of the population accepts this division, players receive the payoffs accordingly, and the game ends. Otherwise, the game continues, and the available resource becomes less valuable. I call the share of the population required to accept the proposal "the size of the minimum winning coalition." This parameter measures how much support a leader needs to stay in power. If it is high or low, the expected ex-ante payoff of each small group is high. If it is medium, the payoff is low. Hence, the model predicts a U-shaped effect of the amount of support a leader needs on the welfare of minorities. To test the model's predictions, I use data on the government representation of ethnic minorities and two indices of executive constraints. The data is cross-national and covers over 20 years. The data shows a U-shaped relationship between the indices of executive constraints and the representation of minorities that the model predicts. The second chapter analyzes media bias in advanced democracies. The main question is whether voters are more competent if there are more media outlets. To understand this relationship, I provide a game-theoretic model of media capture and political persuasion in democratic countries. In the model, there are two politicians, the Incumbent and the Challenger. They co-opt the media by offering them access to information. In exchange, the media support politicians who are available for interviews or include journalists in press pools. Voters choose like-minded media. I show that if the Incumbent is sufficiently popular and has little policy information, then media bias in her favor weakly increases in the number of media outlets. Otherwise, media bias in the Incumbent's favor weakly decreases in the number of media outlets. The welfare of voters weakly increases and decreases in relative cases. The intuition is that, in equilibrium, the Incumbent can co-opt only one media outlet and ensure that enough voters read it. In this case, media outlets compete for access to the Incumbent and agree for a higher bias as their number increases. Another contribution of the chapter is explaining media bias in advanced democracies. Unlike in autocracies, it is hard for politicians to threaten or bribe journalists in such countries. The model in this chapter provides a mechanism of how politicians co-opt journalists using access to information. The third chapter focuses on political disinformation on social media and a potential remedy for it: fact-checking. Political fake news is dangerous for democracies. Social and government pressure made Facebook and Twitter start labeling posts that contain disinformation. However, often a government can not regulate all social media platforms. For instance, the U.S. government can regulate Facebook and Twitter, but not the international Telegram or the Indian Koo. Will making some but not all platforms fact-check increase the probability that voters make the best choice for themselves? If there is no regulation, will social media platforms fact-check? In the third chapter, I propose a game-theoretic model in which two platforms decide whether to fact-check a politician. One of the platforms is ex-ante more attractive to voters than the other. The politician chooses which of the platforms to use for communicating with voters and how often to misrepresent the state of the world if it is bad for her. Making the ex-ante more attractive platform fact-check increases the probability that voters make the best choice given the state of the world. If the politician has a low approval, her policy is unlikely to succeed, or one of the platforms is much more ex-ante attractive, then each platform will choose to fact-check without regulation. Otherwise, neither platform will choose to fact-check.