When Should There Be Vertical Choice in Health Insurance Markets?

We study the welfare effects of offering choice over coverage levels—“vertical choice”—in regulated health insurance markets. We emphasize that heterogeneity in efficient coverage level is not sufficient to motivate choice. When premiums cannot reflect individuals’ costs, it may not be in consumers’ best interest to select their efficient coverage level. We show that vertical choice is efficient only if consumers with higher willingness to pay have a higher efficient level of coverage. We investigate this condition empirically and find that as long as a minimum coverage level can be enforced, the welfare gains from vertical choice are either zero or economically small. (JEL D82, G22, H75, I13, I21)

Economic Analysis of Developing a Sustainable Aviation Fuel Supply Chain Incorporating With Carbon Credits: A Case Study of the Memphis International Airport

Sustainable aviation fuel (SAF) has been considered as a potential means to mitigate greenhouse gas (GHG) emissions from the aviation sector, which is projected to continuously expand. This study examines the impact of developing a SAF sector along with carbon credits on carbon equivalent emissions from aviation using a Stackelberg leader-follower model that accounts for economic interaction between SAF processor and feedstock producers. The modeling framework is applied to an ex-ante optimization of commercial scale SAF production for the Memphis International Airport from the switchgrass-based alcohol-to-jet pathway. Results suggest that supplying 136 million gallons of SAF to the Memphis International Airport annually could reduce 62.5% of GHG emissions compared to conventional jet fuel (CJF). Incorporating with carbon credits, SAF could lower GHG emissions by about 65% in total from displacing CJF and generate additional welfare gains ranging between $12 and $51 million annually compared to the case without carbon credits. In addition, sensitivity analysis suggests advancing SAF conversion rate from biomass could lower the SAF break-even considerably and enhance the competitiveness of SAF over CJF.

Incomplete Exchange Rate Pass-through and International Monetary Policy Cooperation

There is no consensus on the existence of welfare gains from international monetary policy cooperation. This study adds to the debate by providing a new open macroeconomics model with incomplete exchange rate pass-through. We find that, from a global perspective, the welfare gains from international monetary policy cooperation arise with incomplete exchange rate pass-through. Furthermore, the country’s incentive for cooperation increases with its degree of exchange rate pass-through. Cooperation benefits small countries with high pass-through; however, it is disadvantageous to large countries with low pass-through. In addition, when there is in the absence of cooperation, fixed exchange rate regime is preferred for a country suffering from monetary uncertainty, particularly for small economies with high exchange rate pass-through.

Tactical Target Date Funds

We propose target date funds modified to exploit stock return predictability driven by the variance risk premium. The portfolio rule of these tactical target date funds (TTDFs) is extremely simplified relative to the optimal one, making it easy to implement and to communicate to investors. We show that saving for retirement in TTDFs generates economically large welfare gains, even after we introduce turnover restrictions and transaction costs, and after taking into account parameter uncertainty. This predictability also appears to be uncorrelated with individual household risk, suggesting that households are in a prime position to exploit it. This paper was accepted by Tomasz Piskorski, finance.

Spatial Diffusion of E-Commerce in China’s Counties: Based on the Perspective of Regional Inequality

In recent decades, China has been on a new journey toward a digital economy of which e-commerce accounts for a substantial proportion. Despite some controversy, the innovation diffusion hypothesis and efficiency hypothesis of online shopping have been tested in research on the urban–rural dual structure. However, research on the spatial diffusion model of online business is sparse. Based on the online business and online shopping index released by the Ali Research Institute, this article compares the spatial diffusion model of online shopping and online business in the core–periphery structure based on the inequality between the eastern and western regions of China. Our study suggests that online business trends are in line only with the innovation diffusion hypothesis, with marginal counties having lower levels of online business. Online shopping, on the other hand, is in line with the innovation diffusion hypothesis and partially with the efficiency hypothesis, with a higher index of online shopping in the core regions and some peripheral counties. The discrepancy in the spatial diffusion mode is due to the differences in aims and supporting elements between online business and online shopping. Apart from infrastructure, the diffusion of online business is largely constrained by the regional industrial base, while online shopping is influenced by income and savings levels, which is the main reason for the differences in the spatial diffusion of online business and online shopping. We argue that the diffusion of online business has not led to the ability to balance regional inequalities at the national scale, while online shopping has the potential to bridge core and peripheral disparities better than online businesses, not in terms of the ability to bridge economic disparities, but in terms of the potential to reduce spatial consumption inequalities and welfare gains.

Liquidity Constraints in the U.S. Housing Market

We study the severity of liquidity constraints in the U.S. housing market using a life-cycle model with uninsurable idiosyncratic risks in which houses are illiquid, but agents can extract home equity by refinancing their mortgages. The model implies that four-fifths of homeowners are liquidity constrained and willing to pay an average of 13 cents to extract an additional dollar of liquidity from their home. Most homeowners value liquidity for precautionary reasons, anticipating the possibility of income declines and the need to make mortgage payments. The model reproduces well the observed response of consumption to tax rebates and mortgage relief programs and predicts large welfare gains from policies aimed at providing temporary liquidity relief to homeowners.

The Extensive Margin of Exporting Products: A Firm-Level Analysis

To quantify trade frictions, we examine multiproduct exporters. We build a flexible general-equilibrium model and estimate market entry costs using Brazilian firm-product-destination data under rich demand and market access cost shocks. Our estimates show that additional products farther from a firm’s core competency come at higher production costs, but there are substantive economies of scope in market access costs. Market access costs differ across destinations, falling more rapidly in scope at nearby regions and at destinations with fewer nontariff barriers. We evaluate a counterfactual scenario that harmonizes market access costs across destinations and find global welfare gains similar to eliminating all current tariffs. (JEL D22, F12, F13, F14, O14, O19)

Welfare implications of mitigating investment uncertainty

This study explores the welfare implications of mitigating investment uncertainty in the context of Easley and O’Hara (Rev Financ Stud 22:1817–1843, 2009) While one may expect welfare gains by encouraging participation in financial markets by ambiguity-averse investors, we formally show that it hurts other investors and thus is not Pareto-improving without appropriate income transfers. We also examine the welfare effects of income redistribution among heterogeneous investors and government spending on investor education.

Glide paths for a retirement plan with deferred annuities

We construct investment glide paths for a retirement plan using both traditional asset classes and deferred annuities (DAs). The glide paths are approximated by averaging the asset proportions of stochastic optimal investment solutions. The objective function consists of power utility in terms of secured retirement income from purchased DAs, as well as a bequest that can be withdrawn before retirement. Compared with conventional glide paths and investment strategies, our DA-enhanced glide paths provide the investor with higher welfare gains, more efficient investment portfolios and more responsive retirement income patterns and bequest levels to different fee structures and personal preferences.