Benchmarking real-valued acts

A benchmarking procedure ranks real-valued acts by the probability that they outperform a benchmark β which may itself be a random variable; that is, an act f is evaluated by means of the functional V(f)=P(fβ). Expected utility is a special case of benchmarking procedure, where the acts and the benchmark are stochastically independent. This paper provides axiomatic characterizations of preference relations that are representable as benchmarking procedures. The key axiom is the sure-thing principle. When the state space is infinite, different continuity assumptions translate into different properties of the probability P.     

Higher turnout increases incumbency advantages: Evidence from mayoral elections

We analyze the effect of electoral turnout on incumbency advantages by exploring mayoral elections in the German state of Bavaria. Mayors are elected by majority rule in two-round (runoff) elections. Between the first and second ballot of the mayoral election in March 2020, the state government announced an official state of emergency. In the second ballot, voting in person was prohibited and only postal voting was possible. To construct an instrument for electoral turnout, we use a difference-in-differences strategy by contrasting turnout in the first and second ballot in 2020 with the first and second ballots from previous elections. We use this instrument to analyze the causal effect of turnout on incumbent vote shares. A 10-percentage point increase in turnout leads to a statistically robust 3.4 percentage point higher vote share for incumbent mayors highlighting the relevance of turnout-related incumbency advantages.     

Entropy martingale optimal transport and nonlinear pricing–hedging duality

The objective of this paper is to develop a duality between a novel entropy martingale optimal transport (EMOT) problem and an associated optimisation problem. In EMOT, we follow the approach taken in the entropy optimal transport (EOT) problem developed in Liero et al. (Invent. Math. 211:969–1117, 2018), but we add the constraint, typical of martingale optimal transport (MOT) theory, that the infimum of the cost functional is taken over martingale probability measures. In the associated problem, the objective functional, related via Fenchel conjugacy to the entropic term in EMOT, is no longer linear as in (martingale) optimal transport. This leads to a novel optimisation problem which also has a clear financial interpretation as a nonlinear subhedging problem. Our theory allows us to establish a nonlinear robust pricing–hedging duality which also covers a wide range of known robust results. We also focus on Wasserstein-induced penalisations and study how the duality is affected by variations in the penalty terms, with a special focus on the convergence of EMOT to the extreme case of MOT.

     

Corporate investment and stock market valuation

We study the driving forces behind the positive association observed between corporate investment and stock market valuation, and how they interact with managerial equity incentives and informativeness of investment. We build a dynamic model where managers use investment choices to influence investors' opinions about firms' future prospects and increase the market valuation. The incentives to manipulate the valuation processes increase with managerial equity incentives and informativeness of investment. Our empirical findings support the model's predictions that the tendency of using investment to boost market valuation is stronger when managerial stock ownership is high or when earnings quality is low (i.e., there is strong reliance on investment for information).     

Local volatility under rough volatility

Several asymptotic results for the implied volatility generated by a rough volatility model have been obtained in recent years (notably in the small-maturity regime), providing a better understanding of the shapes of the volatility surface induced by rough volatility models, supporting their calibration power to SP500 option data. Rough volatility models also generate a local volatility surface, via the so-called Markovian projection of the stochastic volatility. We complement the existing results on implied volatility by studying the asymptotic behavior of the local volatility surface generated by a class of rough stochastic volatility models, encompassing the rough Bergomi model. Notably, we observe that the celebrated “1/2 skew rule” linking the short-term at-the-money skew of the implied volatility to the short-term at-the-money skew of the local volatility, a consequence of the celebrated “harmonic mean formula” of [Berestycki et al. (2002). Quantitative Finance, 2, 61–69], is replaced by a new rule: the ratio of the at-the-money implied and local volatility skews tends to the constant $1/(H+3/2)$ (as opposed to the constant 1/2), where H is the regularity index of the underlying instantaneous volatility process.     

Enhancing bank transparency: Financial reporting quality,fraudulent peers and social capital

This study examines the role of social norms in financial markets by relating bank transparency to social capital. Using comprehensive data on commercial banks, we provide empirical evidence that high social capital contributes to more transparent financial reporting, thereby enabling more precise risk assessments and promoting financial stability. We find that the effect of social capital is more pronounced when commercial banks are more complex and disclosure incentives of bank managers are strong. Our results suggest that more opaque reporting by peers explains lower transparency but financial misreporting is less contagious when social capital is high. Our study suggests that social capital can effectively improve reporting transparency when other mechanisms are not effective, thus securing financial system stability.     

Farmers’ organizations and sustainable development: An introduction

This special issue features 14 new research papers investigating the role of farmers’ organizations (e.g., collective action, self-help groups, producer companies/organizations, and cooperatives) in supporting sustainable development. The key findings include: (1) farmer groups and cooperatives promote farmers’ adoption of good farm management practices, new agricultural technologies and sustainable farming practices, although not substantially improving farm yield; (2) outsourcing services provided by agricultural cooperatives help to increase the technical efficiency of crop production; (3) cooperative membership enhances members’ bargaining power and enables them to sell their products at higher prices; (4) cooperatives motivate rural laborers to work in off-farm sectors, while self-help groups empower rural women in decision-making; (5) internet use improves agricultural cooperatives’ economic, social, and innovative performances; (6) direct administrative intervention supporting cooperative development may lead to the emergence of shell cooperatives; (7) participation in forest farmer organizations enables wood value chain upgrading; (8) increasing the cooperative size in terms of income, equity, and assets increases the profitability of savings and credit cooperatives; and (9) creating cross-border cooperation between cooperatives generates benefits for all parties involved. These findings can inspire the design of policies aimed to support farmers’ organizations in achieving sustainable development goals.     

Taxation of unhealthy food consumption and the intensive versus extensive margin of obesity

International Tax and Public Finance - If an individual’s health costs are U-shaped in weight with a minimum at some healthy level and if the individual has both self-control problems and...     

Random encounters and information diffusion about product quality

This paper explores how social interactions among consumers shape markets. In a two-country model, consumers meet and exchange information about the quality of the goods. As information spreads, demand evolves, affecting the prices and quantities manufactured by profit-maximizing firms. We show that market prices with informational frictions reach the duopoly price with full information at the limit. However, this convergence can take different paths depending on the size asymmetry between countries. In particular, when the country producing the low-quality good is relatively large, the single market does not immediately turn into a duopoly and can be temporarily trapped in a situation of price instability where no Nash equilibrium in pure (but only in mixed) strategies exists and prices can fluctuate between their monopoly and duopoly levels. It follows that the classical price-reducing effects of international trade may take longer to appear. In view of an intense globalization process, understanding how social meetings affect market outcomes is critical for understanding the performance of international economic integration.     

The optimality of public–private partnerships under financial and fiscal constraints

The government may delegate two sequential tasks (e.g., building and operating an infrastructure) to the same or different agents (i.e., partnership vs. sequential contracts). Agents are risk-neutral but face financial constraints, whereas the government's contractual capacity may be limited by the renegotiation-proofness and fiscal constraints. By relying on history-dependent incentives, the partnership contract corrects moral hazard more effectively than sequential contracts. Thus, it is socially preferred unless bundling different tasks deteriorates the agent's financial conditions. Our results shed new light on the role of firms' financial and government's fiscal conditions in driving the cost–benefit analysis of public–private partnerships.