Economics

The Critical Access Hospital (CAH) program, established under the Balanced Budget Act of 1997, provides cost-based Medicare reimbursement to small rural hospitals in exchange for limits on inpatient capacity and service scope. We estimate the effects of CAH designation on hospital finances, capacity, and organizational outcomes using a synthetic difference-in-differences design that exploits the staggered 1999– 2002 rollout of state-level CAH availability. We find that CAH designation raises operating margins by three to four percentage points, with no change in liquidity or capital investment, as cost-based reimbursement sustains revenue while expenses fall with scale. Designation also re..

Latent-variable models are central to economics but often entail intractable integration. Variational inference (VI), widely used in machine learning, turns this integration into tractable, differentiable optimization by replacing the likelihood with a variational objective. However, guarantees of recovering the true parameters remain limited when the variational family is insufficiently flexible—a key obstacle to the adoption of VI in economics. We first evaluate VI in models of earnings dynamics and show that the choice of variational posterior is crucial. We then introduce indirect variational inference (IVI), which treats VI as an auxiliary model and corrects the bias induced by the va..

Oversight changes the evidence it relies on. We ask when randomized audits and scoring align AI agents that can conceal misconduct and alter records. Stronger auditing makes undeterred violations better hidden. Because the provider writes the agent’s objective, sanctions need not stop at forfeiture, and rare audits deter every type of agent if evidence survives concealment and audit draws cannot be learned in advance. When evidence can be erased, deterrence must come from lower gains from violation, such as credit for stopping, or from costlier or fewer ways to conceal. These conditions identify what failed when agents in OpenAI’s cybersecurity evaluations compromised parts of Hugging Fa..

We show that cross-border learning is an important feature of modern semiconductor manufacturing and that several important channels – such as knowledge sharing along global supply chains, the movement of engineers within multinational firms, and foreign direct investment – operate through market mechanisms rather than anonymous technological spillovers. These findings have significant policy implications. When cross-border learning is mediated by purposeful economic relationships, access to frontier knowledge is neither automatic nor guaranteed. Firms and governments can facilitate - or restrict - the international diffusion of technology, implying that policies to foster domestic techn..