Person:

Gennaioli, N

We present a model of stereotypes in which a decision maker assessing a group recalls only that group’s most representative or distinctive types. Stereotypes highlight differences between groups, and are especially inaccurate (consisting of unlikely, extreme types) when groups are similar. Stereotypical thinking exhibits base rate neglect, but also confirmation bias: beliefs overreact to information that confirms the stereotype and ignore information that contradicts it. Stereotypes can change if new information changes the group’s most distinctive trait. Applied to gender stereotypes, the model provides a unified account of disparate evidence regarding the gender gap in education and in labor markets.

We present a model of market competition and product differentiation in which consumers' attention is drawn to the products' most salient attributes. Firms compete for consumer attention via their choices of quality and price. With salience, strategic positioning of each product affects how all other products are perceived. With this attention externality, depending on the cost of producing quality some markets exhibit "commoditized" price salient equilibria, while others exhibit "de-commoditized" quality salient equilibria. When the cost of producing quality changes, innovation can lead to a radical change in markets. In the context of financial innovation, the model generates the well documented phenomenon of "reaching for yield."

We use a newly assembled sample of 1,503 regions from 82 countries to compare the speed of per capita income convergence within and across countries. Regional growth is shaped by similar factors as national growth, such as geography and human capital. Regional convergence is about 2.5% per year, not more than 1% per year faster than convergence between countries. Regional convergence is faster in richer countries, and countries with better capital markets. A calibration of a neoclassical growth model suggests that significant barriers to factor mobility within countries are needed to account for the evidence.

We present a model of shadow banking in which banks originate and trade loans, assemble them into diversified portfolios, and finance these portfolios externally with riskless debt. In this model: outside investor wealth drives the demand for riskless debt and indirectly for securitization, bank assets and leverage move together, banks become interconnected through markets, and banks increase their exposure to systematic risk as they reduce idiosyncratic risk through diversification. The shadow banking system is stable and welfare improving under rational expectations, but vulnerable to crises and liquidity dry-ups when investors ignore tail risks.