Knowledge that Transforms

In markets for indivisible resources such as workers and objects, subsidy and taxation for an agent may depend on the set of acquired resources and prices. This paper investigates how such transfer policies interfere with the substitutes condition, which is critical for market equilibrium existence and auction mechanism performance among other important issues. For environments where the condition holds in the absence of policy intervention, we investigate which transfer policies preserve the substitutes condition in various economically meaningful settings, establishing a series of characterisation theorems. For environments where the condition may fail without policy intervention, we examine how to use transfer policies to re-establish it, finding exactly when transfer policies based on scales are effective for that purpose. These results serve to inform policymakers, market designers, and market participants of how transfer policies may impact markets, so more informed decisions can be made.

We study policy experimentation in organizations with endogenous membership. An organization decides when to stop a policy experiment based on its results. As information arrives, agents update their beliefs, and enter or leave the organization based on their expected flow payoffs. Unsuccessful experiments make all agents more pessimistic, but also drive out conservative members. We identify sufficient conditions under which the latter effect dominates, leading to excessive experimentation. In fact, the organization may experiment forever in the face of mounting negative evidence. Ex post heterogeneous payoffs exacerbate the problem, as optimists can join forces with guaranteed winners. Control by shareholders who own all future payoffs, however, can have a corrective effect. Our results contrast with models of collective experimentation with fixed membership, in which under-experimentation is the typical outcome.

A widely held view is that small firms in developing countries are prevented from making profitable investments by lack of access to credit and insurance markets. One solution is to provide repayment flexibility in credit contracts. Repayment flexibility eases both the credit constraint, as it allows for increased spending during the start-up phase, and offers insurance, in case of fluctuations in income. In a field experiment among traditional microfinance clients and larger collateralized borrowers in Bangladesh, we randomly assign the option to delay up to 2 monthly repayments at any point during a 12-month loan cycle. The flexible contract leads to substantial improvements in the traditional microfinance clients’ business outcomes, driven by borrowers in the upper tail of the distribution. In addition, we find a significant impact on socio-economic status, combined with lower default rates. We show theoretically and empirically that these effects are induced by an increase in entrepreneurial risk taking, implying that the primary mechanism is insurance provision. Repayment flexibility also attracts less risk-averse borrowers interested in business expansion. At the same time, the effects for the larger loan are much more modest. Our findings suggest that lack of insurance is an important constraint for small firms but that a simple financial product that increases repayment flexibility can be an effective tool for enabling enterprise growth.

We present an experimental framework to study the extent to which failures of contingent thinking explain classic anomalies in a broad class of environments, including overbidding in auctions and the Ellsberg paradox. We study environments in which the subject’s choices affect payoffs only in some states but not in others. We find that anomalies are in large part driven by incongruences between choices in the standard presentation of each problem and a “contingent” presentation, which focuses the subject on the set of states where her actions matter. Additional evidence suggests that this phenomenon is in large part driven by people’s failure to put themselves in states that have not yet happened even though they are made aware that their actions only matter in those states.

We analyse efficient risk-sharing arrangements when the value from deviating is determined endogenously by another risk-sharing arrangement. Coalitions form to insure against idiosyncratic income risk. Self-enforcing contracts for both the original coalition and any coalition formed (joined) after deviations rely on a belief in future cooperation which we term “trust”. We treat the contracting conditions of original and deviation coalitions symmetrically and show that higher trust tightens incentive constraints since it facilitates the formation of deviating coalitions. As a consequence, although trust facilitates the initial formation of coalitions, the extent of risk sharing in successfully formed coalitions is declining in the extent of trust and efficient allocations might feature resource burning or utility burning: trust is indeed a double-edged sword.

A large psychology literature argues that, due to selective memory recall, decision-makers’ forecasts of the future are overly influenced by the perceived news. We adopt the diagnostic expectations (DE) paradigm [Bordalo et al. (2018), Journal of Finance, 73, 199–227] to capture this feature of belief formation, develop a method to incorporate DE in business cycle models, and study the implications for aggregate dynamics. First, we address (1) the theoretical challenges associated with modelling the feedback between optimal actions and agents’ DE beliefs and (2) the time-inconsistencies that arise under distant memory (i.e. when news is perceived with respect to a more distant past than just the immediate one). Second, we show that under distant memory the interaction between actions and DE beliefs naturally generates repeated boom–bust cycles in response to a single initial shock. We also propose a portable solution method to study DE in dynamic stochastic general equilibrium models and use it to estimate a quantitative DE New Keynesian model. Both endogenous states and distant memory play a critical role in successfully replicating the boom–bust cycle observed in response to a monetary policy shock.

This paper shows that more highly concentrated labour markets experience more positive employment effects of the minimum wage. In the most concentrated labour markets, employment rises following a minimum wage increase. The paper establishes its main findings by studying the effects of local minimum wage increases on a key low-wage retail sector, and using data on labour market concentration that covers the entirety of the U.S. with fine spatial variation at the occupation level. The results carry over to the fast-food sector and the entire low-wage labour market and are robust to using proxies of labour market concentration available for a broader range of industries, such as the number of establishments and population density. A model of oligopsonistic competition can explain these effects: there is more room to increase wages in high-concentration areas where wages tend to be further below marginal productivity. These findings provide evidence supporting monopsonistic wage setting as an explanation for the near-zero minimum wage employment effect documented in prior work.

Reclassification risk is a major concern in health insurance where contracts are typically 1 year in length but health shocks often persist for much longer. While most health systems with private insurers pair short-run contracts with substantial pricing regulations to reduce reclassification risk, long-term contracts with one-sided insurer commitment have significant potential to reduce reclassification risk without the negative side effects of price regulation, such as adverse selection. We theoretically characterize optimal long-term insurance contracts with one-sided commitment, extending the literature in directions necessary for studying health insurance markets. We leverage this characterization to provide a simple algorithm for computing optimal contracts from primitives. We estimate key market fundamentals using data on all under-65 privately insured consumers in Utah. We find that dynamic contracts are very effective at reducing reclassification risk for consumers who arrive at the market in good health, but they are ineffective for consumers who come to the market in bad health, demonstrating that there is a role for the government insurance of pre-market health risks. Individuals with steeply rising income profiles find front-loading costly, and thus relatively prefer ACA-type exchanges. Switching costs enhance, while myopia moderately compromises, the performance of dynamic contracts.

In the past three decades, governments in emerging markets have accumulated large amounts of international reserves, especially those with fixed exchange rates. This article proposes a theory of reserve accumulation that can account for these facts. Using a model of endogenous sovereign default with nominal rigidities, we argue that the interaction between sovereign risk and aggregate demand amplification generates a macroeconomic-stabilization hedging role for international reserves. We show that issuing debt to purchase reserves during good times allows the government to stabilize aggregate demand when sovereign spreads rise and rolling over the debt becomes more expensive. We provide empirical evidence consistent with the model’s predictions.

With “2020 hindsight,” the 2000s housing cycle is not a boom–bust but a boom–bust–rebound. Using a spatial equilibrium regression in which house prices are determined by income, amenities, urbanization, and supply, we show that long-run city-level fundamentals predict not only 1997–2019 price and rent growth but also the amplitude of the boom–bust–rebound. This evidence motivates our model of a cycle rooted in fundamentals. Households learn about fundamentals by observing “dividends” but become over-optimistic in the boom due to diagnostic expectations. A bust ensues when beliefs start to correct, exacerbated by a price–foreclosure spiral that drives prices below their long-run level. The rebound follows as prices converge to a path commensurate with higher fundamental growth. The estimated model explains the boom–bust–rebound with a single shock and accounts quantitatively for the dynamics of prices, rents, and foreclosures in cities with the largest cycles. We draw implications for asset cycles more generally.