{"title":"金融投机的宏观经济学","authors":"Alp Simsek","doi":"10.1146/annurev-economics-092120-050543","DOIUrl":null,"url":null,"abstract":"I review the literature on financial speculation driven by belief disagreements from a macroeconomics perspective. To highlight unifying themes, I develop a stylized macroeconomic model that embeds several mechanisms. With short-selling constraints, speculation can generate overvaluation and speculative bubbles. Leverage can substantially inflate speculative bubbles, and leverage limits depend on perceived downside risks. Shifts in beliefs about downside tail scenarios can explain the emergence and the collapse of leveraged speculative bubbles. Speculative bubbles are related to rational bubbles, but they match better the empirical evidence on the predictability of asset returns. Even without short-selling constraints, speculation induces procyclical asset valuation. When speculation affects the price of aggregate assets, it also influences macroeconomic outcomes such as aggregate consumption, investment, and output. Speculation in the boom years reduces asset prices, aggregate demand, and output in the subsequent recession. Macroprudential policies that restrict speculation in the boom can improve macroeconomic stability and social welfare.","PeriodicalId":47891,"journal":{"name":"Annual Review of Economics","volume":null,"pages":null},"PeriodicalIF":6.8000,"publicationDate":"2021-08-05","publicationTypes":"Journal Article","fieldsOfStudy":null,"isOpenAccess":false,"openAccessPdf":"","citationCount":"0","resultStr":"{\"title\":\"The Macroeconomics of Financial Speculation\",\"authors\":\"Alp Simsek\",\"doi\":\"10.1146/annurev-economics-092120-050543\",\"DOIUrl\":null,\"url\":null,\"abstract\":\"I review the literature on financial speculation driven by belief disagreements from a macroeconomics perspective. To highlight unifying themes, I develop a stylized macroeconomic model that embeds several mechanisms. With short-selling constraints, speculation can generate overvaluation and speculative bubbles. Leverage can substantially inflate speculative bubbles, and leverage limits depend on perceived downside risks. Shifts in beliefs about downside tail scenarios can explain the emergence and the collapse of leveraged speculative bubbles. Speculative bubbles are related to rational bubbles, but they match better the empirical evidence on the predictability of asset returns. Even without short-selling constraints, speculation induces procyclical asset valuation. When speculation affects the price of aggregate assets, it also influences macroeconomic outcomes such as aggregate consumption, investment, and output. Speculation in the boom years reduces asset prices, aggregate demand, and output in the subsequent recession. Macroprudential policies that restrict speculation in the boom can improve macroeconomic stability and social welfare.\",\"PeriodicalId\":47891,\"journal\":{\"name\":\"Annual Review of Economics\",\"volume\":null,\"pages\":null},\"PeriodicalIF\":6.8000,\"publicationDate\":\"2021-08-05\",\"publicationTypes\":\"Journal Article\",\"fieldsOfStudy\":null,\"isOpenAccess\":false,\"openAccessPdf\":\"\",\"citationCount\":\"0\",\"resultStr\":null,\"platform\":\"Semanticscholar\",\"paperid\":null,\"PeriodicalName\":\"Annual Review of Economics\",\"FirstCategoryId\":\"96\",\"ListUrlMain\":\"https://doi.org/10.1146/annurev-economics-092120-050543\",\"RegionNum\":2,\"RegionCategory\":\"经济学\",\"ArticlePicture\":[],\"TitleCN\":null,\"AbstractTextCN\":null,\"PMCID\":null,\"EPubDate\":\"\",\"PubModel\":\"\",\"JCR\":\"Q1\",\"JCRName\":\"ECONOMICS\",\"Score\":null,\"Total\":0}","platform":"Semanticscholar","paperid":null,"PeriodicalName":"Annual Review of Economics","FirstCategoryId":"96","ListUrlMain":"https://doi.org/10.1146/annurev-economics-092120-050543","RegionNum":2,"RegionCategory":"经济学","ArticlePicture":[],"TitleCN":null,"AbstractTextCN":null,"PMCID":null,"EPubDate":"","PubModel":"","JCR":"Q1","JCRName":"ECONOMICS","Score":null,"Total":0}
I review the literature on financial speculation driven by belief disagreements from a macroeconomics perspective. To highlight unifying themes, I develop a stylized macroeconomic model that embeds several mechanisms. With short-selling constraints, speculation can generate overvaluation and speculative bubbles. Leverage can substantially inflate speculative bubbles, and leverage limits depend on perceived downside risks. Shifts in beliefs about downside tail scenarios can explain the emergence and the collapse of leveraged speculative bubbles. Speculative bubbles are related to rational bubbles, but they match better the empirical evidence on the predictability of asset returns. Even without short-selling constraints, speculation induces procyclical asset valuation. When speculation affects the price of aggregate assets, it also influences macroeconomic outcomes such as aggregate consumption, investment, and output. Speculation in the boom years reduces asset prices, aggregate demand, and output in the subsequent recession. Macroprudential policies that restrict speculation in the boom can improve macroeconomic stability and social welfare.
期刊介绍:
The Annual Review of Economics covers significant developments in the field of economics, including macroeconomics and money; microeconomics, including economic psychology; international economics; public finance; health economics; education; economic growth and technological change; economic development; social economics, including culture, institutions, social interaction, and networks; game theory, political economy, and social choice; and more.