We propose a novel methodology for evaluating the accuracy of numerical solutions to dynamic economic models. It consists in constructing a lower bound on the size of approximation errors. A small lower bound on errors is a necessary condition for accuracy: If a lower error bound is unacceptably large, then the actual approximation errors are even larger, and hence, the approximation is inaccurate. Our lower‐bound error analysis is complementary to the conventional upper‐error (worst‐case) bound analysis, which provides a sufficient condition for accuracy. As an illustration of our methodology, we assess approximation in the first‐ and second‐order perturbation solutions for two stylized models: a neoclassical growth model and a new Keynesian model. The errors are small for the former model but unacceptably large for the latter model under some empirically relevant parameterizations.
We set out in this study to investigate whether bancassurance business leads to improvements in the efficiency and profitability of banks. We examine the positive impacts on the system using actual data provided by a unique database on banks engaging in bancassurance business in Taiwan between 2004 and 2012. Our results reveal that banks with greater involvement in bancassurance business generally tend to experience improvements in their efficiency, and thus also accrue greater profits. Our empirical results provide evidence to support that bancassurance business offers substantial benefits for banks, ultimately leading to an increase in shareholder value. Finally, our results also reveal that the adoption of a diversification strategy in bancassurance can impact bank performance.
We use institutional trading data to examine whether skilled institutions exploit positive abnormal ex‐dividend returns. Results show that institutions concentrate trading around certain ex‐dates, and earn higher profits around these events. Dividend capture trades represent 6% of all institutional buy trades but contribute 15% of overall abnormal returns. Institutional dividend capture trading is persistent. Institutional ex‐day profitability is also strongly cross‐sectionally related to trade execution skill. The relation between execution skill and profits disappears around placebo non‐ex‐days. Results suggest that skilled institutions target certain opportunities rather than benefiting uniformly over time. Furthermore, only skilled institutions can profit from dividend capture.
1-share trades are the most common odd lot trade size, accounting for 9.62% of all odd lot transactions and 3.65% of all trades on NASDAQ in 2012. While 50.41% of 1-share trades result from broken orders, 34.89% of 1-share trades are intentional. We provide substantial evidence that traders use 1-share trades to “ping” for hidden liquidity. In particular, our results indicate that 1-share trades are disproportionately aggressive and also execute against hidden liquidity more than any other odd lot trade size. We also find a relative increase in trading immediately following a 1-share trade. Our results are in line with Clark-Joseph (2014), who suggests that traders may use small, unprofitable trades to detect information from other traders. Specifically, 1-share trades represent the minimum cash outlay necessary to trade, while simultaneously producing the smallest possible effects on a market maker's inventory, and in turn, a security's price.
We use variation in historical state centralization to examine the long-term impact of institutions on cultural norms. The Kuba Kingdom, established in Central Africa in the early 17th century by King Shyaam, had more developed state institutions than the other independent villages and chieftaincies in the region. It had an unwritten constitution, separation of political powers, a judicial system with courts and juries, a police force, a military, taxation, and significant public goods provision. Comparing individuals from the Kuba Kingdom to those from just outside the Kingdom, we find that centralized formal institutions are associated with weaker norms of rule following and a greater propensity to cheat for material gain. This finding is consistent with recent models where endogenous investments to inculcate values in children decline when there is an increase in the effectiveness of formal institutions that enforce socially desirable behavior. Consistent with such a mechanism, we find that Kuba parents believe it is less important to teach children values related to rule-following behaviors.
We track high-growth ventures from the idea stage to commercialization and investigate the nature of the gender gap early in the venture lifecycle. Using data on 651 venture ideas that collectively attracted over $700 million in venture financing, we find a significant gender gap among ventures without documented intellectual assets at the earliest stage of founding but not among ventures that already possess intellectual assets. We also find a gender gap in entrepreneurs' readiness to commit to their venture ideas full-time. Conditional on such commitment, there are no significant differences in ventures' access to venture financing or rate of commercialization.
Between 1990 and 2015, Indonesia lost nearly 25 percent of its forests, largely due to intentional burning to clear land for cultivation of palm oil and timber plantations.1 The neighboring "victim countries" experienced severe deteriorations in air quality as a result of these fires. For example, Singapore experienced record air pollution levels in June of 2013 and again in September of 2015 as a result of the Indonesian forest fires.2 This air pollution is associated with increased incidences of upper respiratory tract infections, acute conjunctivitis, lung disease, asthma, bronchitis, emphysema, and pneumonia, among other ailments.2 Quantifying the impact of air pollution on health outcomes is challenging because pollution levels are often nonrandom for a variety of reasons, including policy endogeneity and sorting (Dominici, Greenstone, and Sunstein 2014). In this paper we offer the first causal analysis of the transboundary health effects of the Indonesian forest burning. The Indonesian fires induce exogenous variation in Singaporean air quality. We take advantage of this by using satellite fire data to instrument for changes in Singaporean air quality. Since Singapore is only 277.6 square miles in area (two-thirds the size of New York City), air pollution resulting from the fires is homogeneously spread so that sorting is less likely to be an issue. Using a two-stage least squares approach, we find that from 2010 through mid-2016, the Indonesian fires caused a statistically significant increase in pollution levels in Singapore. Our study also provides evidence that polyclinic attendances for acute respiratory tract infections and acute conjunctivitis in Singapore increased as a result of the deterioration in air quality. The reduced form estimates show that a one standard deviation increase in our measure of fires causes a 0.7 standard deviation increase in polyclinic attendances for each of these illnesses. These findings provide causal evidence of the transboundary pollution and health impacts of the Indonesian forest burning on neighboring Singapore.
American Economic Review2017107(5), 136-140open access
We report on two experiments investigating whether there is a gender difference in the willingness to compete against oneself (self-competition), similar to what is found when competing against others (other-competition). In one laboratory and one online market experiment, involving a total of 1,200 participants, we replicate the gender-gap in willingness to other-compete but find no evidence of a gender difference in the willingness to self-compete. We explore the roles of risk and confidence and suggest that these factors can account for the different findings. Finally, we document that self-competition does no worse than other-competition in terms of performance boosting.
American Economic Review2017107(5), 282-286open access
Policymakers often consider interventions at the scale of the population, or some other large scale. One of the sources of information about the potential effects of such interventions is experimental studies conducted at a significantly smaller scale. A common occurrence is for the treatment effects detected in these small-scale studies to diminish substantially in size when applied at the larger scale that is of interest to policymakers. This paper provides an overview of the main reasons for a breakdown in scalability. Understanding the principal mechanisms represents a first step toward formulating countermeasures that promote scalability.
Economics challenge the specification of discretionary accrual models. Since rent-seeking firms pursue differentiated business strategies, firms in the same industry experience idiosyncratic shocks due to heterogeneous economic fundamentals and hence have different accrual-generating processes. We present evidence that idiosyncratic shocks are widespread, propagate through multiple years of financial statements, and reduce accrual models' goodness of fit. This not only affects abnormal accrual estimates for the firm experiencing shocks, but also affects measurement of abnormal accruals for other firms in the industry. We show that idiosyncratic shocks not only add noise to abnormal accruals, but can also exacerbate bias in both unsigned and signed abnormal accruals. We propose ways to reduce accrual model misspecification.