La plupart des informations présentées ci-dessous ont été récupérées via RePEc avec l'aimable autorisation de Christian Zimmermann
Black-Scholes Approximation of Warrant Prices: Slight Return in a Low Interest Rate EnvironmentJournal articlePhilippe Bertrand, Annals of Operations Research, Forthcoming

The objective of this paper is to emphasize the differences between a call and a warrant as well as the different valuation methods of warrants which have been introduced in the financial literature. For the sake of simplicity and applicability, we only consider a debt-free equity-financed firm. More recently a formal distinction between structural and reduced form pricing models has been introduced. This distinction is important whether one wishes to price a new warrant issue or outstanding warrants. If we are interested in pricing a new issue of warrants, e.g. in the context of a management incentive package, one has to rely on a structural model. However most of practitioners use the simple Black-Scholes formula. In this context, we analyze the accuracy of the approximation of the “true” price of a warrant by the Black-Scholes formula. We show that in the current low interest rate environment, the quality of the approximation deteriorates and the sensitivity of this approximation to the volatility estimate increases.

Profit Effects of Consumers’ Identity Management: A Dynamic ModelJournal articleDidier Laussel, Ngo Van Long et Joana Resende, Management Science, Forthcoming

We consider a nondurable good monopolist that collects data on its customers in order to profile them and subsequently practice price discrimination on returning customers. The monopolist’s price discrimination scheme is leaky in the sense that an endogenous fraction of consumers choose to incur a privacy cost to conceal their identity when they return in the following periods. We characterize the Markov perfect equilibrium of the game under two alternative customer profiling regimes: full information acquisition (FIA) and purchase history information (PHI). In both cases, we find that, contrary to what could be expected, the monopolist’s aggregate profit is not monotonically increasing in the level of the privacy cost, but a U-shaped function of it, leading to ambiguous profit effects: a reduction in privacy costs increases the fraction of customers who choose to be anonymous (detrimental profit effect), but it also softens the firm’s introductory price, reducing the pace at which prices targeted to new customers fall over time (positive profit effect). When comparing results under FIA and PHI, we find that market expansion is faster, and more customers conceal their identity under FIA than under PHI. Equilibrium profits are also higher in the FIA case. Although equilibrium profits are U-shaped functions of the privacy cost in both profiling regimes, they tend to be globally decreasing with the privacy cost under PHI and globally increasing under FIA.

This paper was accepted by Eric Anderson, marketing.

A novel community-based therapeutic education program for reducing alcohol-related harms and stigma in people with alcohol use disorders: A quasi-experimental study (ETHER study)Journal articleTangui Barré, Clémence Ramier, Saskia Antwerpes, Marie Costa, Morgane Bureau, Gwenaelle Maradan, Vincent Di Beo, Christophe Cutarella, Jacques Leloutre, Olivier Riccobono-Soulier, et al., Drug and Alcohol Review, Volume n/a, Issue n/a, Forthcoming

Introduction Alcohol use disorder (AUD) is associated with a significant disease burden in France, where alcohol use is deeply rooted in culture. However, the treatment gap is large because of several barriers, including stigmatisation and drinkers' apprehension about total abstinence. However, standardised and evidence-based interventions based on controlled-drinking for people with AUD are lacking. We aimed to assess the effectiveness of a novel community-based French therapeutic patient education (TPE) program for people with AUD named Choizitaconso. Methods A before-after non-randomised quasi-experimental study, named ETHER, was designed and implemented with people living with AUD, over a period of 6 months. The primary outcome was percentage change in the number of alcohol-related harms experienced. Secondary outcomes were percentage changes in psycho-social patient-reported and community-validated outcomes. Participants in the intervention group (n = 34) benefited from the 10-week TPE program Choizitaconso, while the comparison group (n = 58) received standard care. The Kruskall–Wallis and chi-squared or Fisher's exact tests were used to compare before-after changes in variables in both groups. Linear regression models were used to test for the effect of study group on each outcome and to test for the effect of alcohol consumption as a confounder. Results At 6 months, all outcomes but one either remained stable or numerically improved in both groups. Internalised stigma significantly improved in the intervention group (p = 0.026) but not in the comparison group (p = 0.207), with a significant group effect (p = 0.014). Discussion and Conclusions This study demonstrates the effectiveness of the Choizitaconso TPE program on community-validated outcomes, especially internalised stigma.

Production Networks and International Fiscal SpilloversJournal articleMichael B. Devereux, Karine Gente et Changhua Yu, The Economic Journal, pp. uead014/online2023-01-30, Forthcoming

This paper analyzes the impact of fiscal spending shocks in a dynamic, multi-country model with international production networks. The response of real GDP to a fiscal spending shock can be decomposed into a Direct, Income, and Price effect. The Direct Effect depends only on input-output linkages, while the Price Effect is zero in the aggregate. We apply this decomposition to the Eurozone, and find that fiscal spillovers from Germany and the core Eurozone countries can be large, and within the range of empirical estimates. Without international production networks, spillovers would be significantly smaller. In an empirical application using the decomposition we find results strongly consistent with the model.

Accounting for subsistence needs in non-market valuation: a simple proposalJournal articleVictor Champonnois et Olivier Chanel, Journal of Environmental Planning and Management, pp. 1-24, Forthcoming

Revealed and stated preference techniques are widely used to assess willingness to pay (WTP) for non-market goods as input to public and private decision-making. However, individuals first have to satisfy subsistence needs through market good consumption, which affects their ability to pay. We provide a methodological framework and derive a simple ex post adjustment factor to account for this effect. We quantify its impacts on the WTP for non-market goods and the ranking of projects theoretically, numerically and empirically. This confirms that non-adjusted WTP tends to be plutocratic: the views of the richest – whatever they are – are more likely to impact decision-making, potentially leading to ranking reversal between projects. We also suggest that the subsistence needs-based adjustment factor we propose has a role to play in value transfer procedures. The overall goal is a better representation of the entire population’s preferences with regard to non-market goods.

Does Affective Forecasting Error Induce Changes in Preferences? Lessons from Danish Soldiers Anticipating Combat in AfghanistanJournal articleOlivier Chanel, Stéphanie Vincent Lyk-Jensen et Jean-Christophe Vergnaud, Defence and Peace Economics, pp. 1-24, Forthcoming

This paper investigates how affective forecasting errors (A.F.E.s), the difference between anticipated emotion and the emotion actually experienced, may induce changes in preferences on time, risk and occupation after combat. Building on psychological theories incorporating the role of emotion in decision-making, we designed a before-and-after-mission survey for Danish soldiers deployed to Afghanistan in 2011. Our hypothesis of an effect from A.F.E.s is tested by controlling for other mechanisms that may also change preferences: immediate emotion, trauma effect – proxied by post-traumatic stress disorder (P.T.S.D.) – and changes in wealth and risk perception. At the aggregate level, results show stable preferences before and after mission. We find positive A.F.E.s for all three emotions studied (fear, anxiety and excitement), with anticipated emotions stronger than those actually experienced. We provide evidence that positive A.F.E.s regarding fear significantly increase risk tolerance and impatience, while positive A.F.E.s regarding excitement strengthen the will to stay in the military. Trauma has no impact on these preferences.

Agency Independence, Campaign Contributions, and Favoritism in US Federal Government ContractingJournal articleMihály Fazekas, Romain Ferrali et Johannes Wachs, Journal of Public Administration Research and Theory, pp. muac026, Forthcoming

The impacts of money in US politics have long been debated. Building on principal-agent models, we test whether and to what degree companies’ political donations lead to their favored treatment in federal procurement. We expect the impact of donations on favoritism to vary by the strength of control by political principals over their bureaucratic agents. We compile a comprehensive dataset of published federal contracts and registered campaign contributions for 2004–15. We develop risk indices capturing tendering practices and outcomes likely characterized by favoritism. Using fixed effects regressions, matching, and regression discontinuity analyses, we find confirming evidence for our theory. A large increase in donations from $10,000 to $5m (in USD) increases favoritism risks by about 1/4th standard deviation (SD). These effects are largely partisan, with firms donating to the party that holds the presidency showing higher risk. Donations influence favoritism risks most in less independent agencies: the same donation increases the risk of favoritism by an additional 1/3rd SD in agencies least insulated from politics. Exploiting sign-off thresholds, we demonstrate that donating contractors are subject to less scrutiny by political appointees.

A subgradient method with non-monotone line searchJournal articleOrizon P. Ferreira, Geovani N. Grapiglia, E. M. Santos et João Carlos O. Souza, Computational Optimization and Applications, Forthcoming

In this paper we present a subgradient method with non-monotone line search for the minimization of convex functions with simple convex constraints. Different from the standard subgradient method with prefixed step sizes, the new method selects the step sizes in an adaptive way. Under mild conditions asymptotic convergence results and iteration-complexity bounds are obtained. Preliminary numerical results illustrate the relative efficiency of the proposed method.

The Macroeconomic Impact of the 1918–19 Influenza Pandemic in SwedenJournal articleMartin Karlsson, Mykhailo Matvieiev et Maksym Obrizan, The B.E. Journal of Macroeconomics, Forthcoming

In this paper, we develop an overlapping generations model with endogenous fertility and calibrate it to the Swedish historical data in order to estimate the economic cost of the 1918–19 influenza pandemic. The model identifies survivors from younger cohorts as main benefactors of the windfall bequests following the influenza mortality shock. We also show that the general equilibrium effects of the pandemic reveal themselves over the wage channel rather than the interest rate, fertility or labor supply channels. Finally, we demonstrate that the influenza mortality shock becomes persistent, driving the aggregate variables to lower steady states which costs the economy 1.819% of the output loss over the next century.

Valuation of ecosystem services and social choice: the impact of deliberation in the context of two different aggregation rulesJournal articleMariam Maki Sy, Charles Figuières, Hélène Rey-Valette, Richard B. Howarth et Rutger De Wit, Social Choice and Welfare, Forthcoming

This paper describes an empiric study of aggregation and deliberation—used during citizens’ workshops—for the elicitation of collective preferences over 20 different ecosystem services (ESs) delivered by the Palavas coastal lagoons located on the shore of the Mediterranean Sea close to Montpellier (S. France). The impact of deliberation is apprehended by comparing the collectives preferences constructed with and without deliberation. The same aggregation rules were used before and after deliberation. We compared two different aggregation methods, i.e. Rapid Ecosystem Services Participatory Appraisal (RESPA) and Majority Judgement (MJ). RESPA had been specifically tested for ESs, while MJ evaluates the merit of each item, an ES in our case, in a predefined ordinal scale of judgment. The impact of deliberation was strongest for the RESPA method. This new information acquired from application of social choice theory is particularly useful for ecological economics studying ES, and more practically for the development of deliberative approaches for public policies.