Free entry into markets with decreasing average costs and differentiated products can result in an inefficient number of firms and suboptimal product variety. Because new firms and products draw their customers in part from existing products, concentration can affect incentives to enter as well...

This paper investigates the effects of state censorship of opposition media using evidence from the closing of RCTV, a popular opposition television channel in Venezuela. The government did not renew RCTV's license, and the channel was replaced overnight, during May 2007, by a pro-government...

In theory, free entry can lead to social inefficiency. When new products are substitutes for existing products, the business stolen from incumbents places a wedge between private and social benefits of entry. The business stealing effect can be offset if entry reduces prices or increases...

This paper measures for the first time the economic efficiency effects of the taxation of wireless services, which are taxed by federal, state, and local governments at relatively high rates in the range of 14%-25%. The paper concludes such taxes are a much greater drain on the economy than...

The COVID-19 pandemic has devastated many low- and middle-income countries (LMICs), causing widespread food insecurity and a sharp decline in living standards. In response to this crisis, governments and humanitarian organizations worldwide have mobilized targeted social assistance programs....

Information is a crucial ingredient in economic decision making. Yet measuring the extent of information exchange among individuals and its effect on economic outcomes is a difficult task. We use the universe of de-identified cellphone usage records from more than one million users in a Chinese...

We introduce a novel measure of segregation, experienced isolation, that captures individuals' exposure to diverse others in the places they visit over the course of their days. Using Global Positioning System (GPS) data collected from smartphones, we measure experienced isolation by race. We...

Traveling beyond the immediate surroundings of one's residence can lead to greater exposure to new ideas and information, jobs, and greater transmission of disease. In this paper, we document the geographic mobility of individuals in the U.S., and how this mobility varies across U.S. cities,...

We study the effect of information on technology adoption and productivity in agriculture. Our empirical strategy exploits the expansion of the mobile phone network in previously uncovered areas of rural India coupled with the availability of call centers for agricultural advice. We measure...

Mobile money is a tool that allows individuals to make financial transactions using cell phone technology. In this paper, we report initial results of two rounds of a large survey of households in Kenya, the country that has seen perhaps the most rapid and widespread growth of a mobile money...