Rapid population growth in many developing countries has raised concerns regarding food security and household welfare. To understand the consequences of population growth in a general equilibrium setting, this paper examines the dynamics of population density and its impacts on household...

Electric vehicle (EV) battery costs have declined by more than 90% over the past decade. This study investigates the role of learning-by-doing (LBD) in driving this reduction and its interaction with two major government policies - consumer EV subsidies and local content requirements. Leveraging...

This paper examines the impact of industrial policies (IPs) on innovation in the global automobile industry. We compile the first comprehensive dataset linking global IPs with patent data related to the auto industry from 2008 to 2023. We document a major shift in policy focus: by 2022, nearly...

Industrial policy has been used throughout history in some form or other by most countries. Yet, it remains one of the most contentious issues among policymakers and economists alike. In part, this is because the empirical evidence on whether and how it should be implemented remains slim. Scant...

Concerns over the excessive use of mobile phones, especially among youths and young adults, are growing. We present, to our knowledge, the first estimates of both behavioral spillover and contextual peer effects, as well as the first comprehensive evidence of how own and peers' mobile app usage...

The social costs of pollution and climate change hinge critically on humans' ability to adapt. Based on transaction records from the world's largest payment network, this research compiles daily travel flows and documents that China's rapid expansion of high-speed railways (HSR) facilitates the...

Attribute-based subsidies (ABS) are commonly used to promote the diffusion of energy-efficient products, whose manufacturers often wield significant market power. We develop a theoretical framework for the optimal design of ABS to account for endogenous product attributes, environmental...

The Hub-and-Spoke network is a defining feature of the airline industry. This paper is among the first in the literature to introduce an empirical framework for analyzing network competition among airlines. Airlines make market entry decisions and choose flight frequencies in the first stage,...