Publications

Abstract Face à l’irruption de la Covid-19, ont surgi des demandes urgentes de prédire, d’expliquer et de faire comprendre sa diffusion aussi bien géographique que sociale, notamment lorsqu’il s’agissait de soutenir telle ou telle décision politique ou de santé publique (distanciations, confinement, etc.). Plusieurs modèles computationnels – en particulier à agents – ont été bien vite mis en avant. Mais dans quelle mesure sont-ils réellement à même de remplir de telles fonctions, en particulier dans un contexte aussi contraint et variable ? Ce livre propose un ensemble d’analyses précieuses et salutaires pour qui voudra former son jugement à ce sujet. Il s’appuie sur des exemples et des analyses de plusieurs modèles de diffusion de la Covid-19, dont certains ont été utilisés par les pouvoirs publics. Il propose aussi des modèles alternatifs, dont certains inédits. Il s’adresse à un large lectorat. Les analyses techniques y sont effectuées avec beaucoup de pédagogie, sans sacrifier à la précision. Elles peuvent donc intéresser les concepteurs et utilisateurs de modèles, les étudiants, les élus, les associations concernées et tout citoyen soucieux de comprendre ces outils omniprésents. Au-delà du cas de la Covid-19, on y trouve une mise en perspective et une discussion plus générale concernant l’usage des modèles formels en sciences sociales, en particulier dans le cadre de l’aide à la décision publique. Analysant le contexte de la crise que l’on traverse, les auteurs évitent de donner un point de vue personnel, mais au contraire tentent d’aider chacun à avancer dans sa propre réflexion, en mettant en avant les questionnements qui peuvent s’adosser aux modèles présentés. L’ouvrage comprend deux parties : l’une qui propose une analyse critique de modèles existants, l’autre prenant la forme de trois propositions de modèles qui permettent de percevoir la richesse et la multiplicité des modèles agents de diffusion de maladie – à la fois dans leur conception et leur manipulation. Un glossaire et un intermède sur les « apports des modèles agents en général et pour la Covid-19 en particulier » replacent ces réflexions dans le cadre plus large de la simulation agents appliquée aux sciences sociales.
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Abstract Background. Many cancer survivors experience late effects of cancer treatment and therefore struggle to return to work. Norway provides rehabilitation programs to increase labor force participation for cancer survivors after treatment. However, the extent to which such programs affect labor force participation has not been appropriately assessed. This study aims to investigate i) labor force participation, sick leave and disability rates among cancer survivors up to 10 years after being diagnosed with cancer and identify comorbidities contributing to long-term sick leave or disability pensioning; ii) how type of cancer, treatment modalities, employment sectors and financial- and sociodemographic factors may influence labor force participation; iii) how participation in rehabilitation programs among cancer survivor affect the longterm labor force participation, the number of rehospitalizations and incidence of comorbidities. Design and methods. Information from four medical, welfare and occupational registries in Norway will be linked to information from 163,279 cancer cases (15.68 years old) registered in the Norwegian Cancer Registry from 2004 to 2016. The registries provide detailed information on disease characteristics, comorbidities, medical and surgical treatments, occupation, national insurance benefits and demographics over a 10-year period following a diagnosis of cancer. Expected impact of the study for Public Health. The study will provide important information on how treatment, rehabilitation and sociodemographic factors influence labor force participation among cancer survivors. Greater understanding of work-related risk factors and the influence of rehabilitation on work-participation may encourage informed decisions among cancer patients, healthcare and work professionals and service planners.
Keywords HEALTH PROMOTION, Return to work, Sick leave, Social security, Disease
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Abstract The aim of this paper is to investigate the impact of remittances outflows on inflation for a panel of 14 OPEC countries during the period 1980-2018. Using bias-corrected least-squares dummy variable (CLSDV) estimator, empirical results reveal that remittance outflows have no effect on inflation rate. However, trade openness and current account deficits have a positive impact on inflation. Further, oil price appears to not have any effect on inflation in OPEC countries.
Keywords CLSDV, Inflation, OPEC, Remittances
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Abstract The Great Recession has strongly influenced employment patterns across skill and gender groups in EU countries. We analyse how these changes in workforce composition might distort comparisons of conventional measures of gender wage gaps via non-random selection of workers into EU labour markets. We document that male selection (traditionally disregarded) has become positive during the recession, particularly in Southern Europe. As for female selection (traditionally positive), our findings are twofold. Following an increase in the labour-force participation of less-skilled women, due to an added-worker effect, these biases declined in some countries where new female entrants were able to find jobs, whereas they went up in other countries which suffered large female employment losses. Finally, we document that most of these changes in selection patterns were reversed during the subsequent recovery phase, confirming their cyclical nature.
Keywords Gender employment gaps, Gender wage gaps, Sample selection
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Abstract The standard forms of bootstrap iteration are very computationally demanding. As a result, there have been several attempts to alleviate the computational burden by use of approximations. In this paper, we extend the fast double bootstrap of Davidson and MacKinnon (2007) to higher orders of iteration, and provide algorithms for their implementation. The new methods make computational demands that increase only linearly with the level of iteration, unlike standard procedures, whose demands increase exponentially. In a series of simulation experiments, we show that the fast triple bootstrap improves on both the standard and fast double bootstraps, in the sense that it suffers from less size distortion under the null with no accompanying loss of power.
Keywords Fast iterated bootstrap, Bootstrap iteration, Bootstrap iteration Fast iterated bootstrap
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Abstract Measuring Economic Growth and Productivity is not only a book on an essential topic, namely that of "growth and productivity", it is also a fabulous ensemble, bringing together contributions from many top specialists. But, in addition, it is a tribute to Dale W. Jorgenson, who has for decades been an exceptional contributor to gaining a better knowledge of the mechanisms of growth and productivity. The volume is dedicated to him. I was present in January 2020 at the annual IPM dinner at the AEA conference, when a preprint of the book was presented to him by the editor, Barbara Fraumeni. I openly admit that it was a very emotional moment.
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Abstract Background: Ageing populations and rising prevalence of non-communicable diseases (NCDs) increasingly contribute to the growing cost burden facing European healthcare systems. Few studies have attempted to quantify the future magnitude of this burden at the European level, and none of them consider the impact of potential changes in risk factor trajectories on future health expenditures. Methods: The new microsimulation model forecasts the impact of behavioural and metabolic risk factors on NCDs, longevity and direct healthcare costs, and shows how changes in epidemiological trends can modify those impacts. Economic burden of NCDs is modelled under three scenarios based on assumed future risk factors trends: business as usual (BAU); best case and worst case predictions (BCP and WCP). Findings: The direct costs of NCDs in the EU 27 countries and the UK (in constant 2014 prices) will grow under all scenarios. Between 2014 and 2050, the overall healthcare spending is expected to increase by 0.8% annually under BAU. In the all the countries, 605 billion Euros can be saved by 2050 if BCP is realized compared to the BAU, while excess spending under the WCP is forecast to be around 350 billion. Interpretation: Although the savings realised under the BCP can be substantial, population ageing is a stronger driver of rising total healthcare expenditures in Europe compared to scenario-based changes in risk factor prevalence.
Keywords Obesity, Cardiovascular disease risk, Cancer risk factors, Noncommunicable diseases, European union, Medical risk factors, Europe, Health economics
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Abstract This study assesses the effect of an economy’s business environment on the ability of firms to be part of a global value chain (GVC). With the use of a comprehensive firm-level dataset from the World Bank Enterprise Survey—and with a special focus on the countries of the Middle East and North Africa and East Asia and Pacific regions—the contribution of the paper is threefold: First, it provides a range of measures of the characteristics of firms that would identify a firm as likely to be integrated into a GVC. Second, it examines the association between an array of business environment variables—infrastructure; access to finance; fiscal policy; enforcement of contracts; ease of obtaining permits; extent of the informal sector; trade procedures; and firm and investor security—and the likelihood of a firm’s being integrated into a GVC. Third, we examine these effects separately for small and large firms and for sectors with high and low tariffs. Our main findings show that, in general, the number of days that are required to pay taxes, the number of procedures that are necessary to register property, and the time to export and to import have a significantly negative association with the likelihood of a firm’s integration into a GVC. More heterogeneity is observed at the regional level, at the firm size level, and for sectors with high versus low tariffs.
Keywords Business environment, Firms, Global value chains
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Abstract Around 50% of individuals obtain or hear about jobs through social networks. This hiring trend may become problematic when the labor market is tight and people need less social contacts to find a job. Using a one-period static model where network members may receive job offers directly from the firm or indirectly through employed members in the network we show that the share of new hires finding a job through social connections (ie network matching rate) decreases with the job finding rate. Using French data for the period 2003-2012, we test this prediction with immigrants, a population subgroup for whom networks play a major role in occupational decisions. We propose two network matching rate indicators, one based on direct recommendations and another one internalizing the positive externality on the employment probability induced by peers. We find a decreasing relationship between the network matching rate and the job finding rate. Social connections are less helpful for finding jobs during economic expansions.
Keywords Immigrant, Network matching rate, Economic cycle
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Abstract Information provision is a relatively recent but steadily growing environmental policy tool. Its emergency and topicality are due to the current escalation of ecological threats. Meanwhile, its high complexity and flexibility require a comprehensive approach to its design, which has to be tailored for specific characteristics of production process, market structure, and regulatory goals. This work proposes such an approach and builds a framework based on a three-level mathematical program extending well-known two-level Stackelberg game by introducing one more economic agent and one extra level of this sequential game. This study provides simple and very intuitive algorithms to compute optimal multi-tier information provision policies, both mandatory and voluntary. The paper urges for the wide implementation of such efficient environmental policy design tools.
Keywords Eco-labelling, Eco-certification, Information provision, Environmental policy, Exact algorithms, Multi-level mathematical programming, Stackelberg game
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Abstract I develop a model of activism and polarization in the context of electoral competition. Two candidates simultaneously announce policy platforms and seek the support of ideologically inclined activists. Activists compete to influence electoral outcomes by expending costly support for their respective candidates. The presence of activists always moderates the platform choice of candidates, compared to the case of no activism. The central finding of the paper is that the relationship between partisanship of activists and polarization is ambiguous. As activists become increasingly partisan, polarization of candidate platforms reduces or widens depending on the costs of activism. I present normative conditions under which the presence of activism and increased partisanship among activists are both welfare-improving for voters. Finally, introducing a public funding option for candidates increases polarization in the political process.
Keywords Public funding, Polarization, Influence seeking, Downsian competition, Activism
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Abstract Objective: To evaluate the impact of infertility and Medically Assisted Reproduction (MAR) throughout all aspects of life among infertile women and men. Materials and methods: An online survey included 1 045 French patients (355 men, 690 women) who were living or had lived the experience of infertility and MAR. The questionnaire included 56 questions on several domains: global feelings, treatment burden, rapport with medical staff, psychosocial impact, sexual life and professional consequences. Results: Respondents had experienced an average of 3.6 (95% CI: 3.3–3.9) MAR cycles: 5% (n = 46) were pregnant, 4% (n = 47) were waiting to start MAR, 50% (n = 522) succeeded in having a live birth following MAR, 19% (n = 199) were currently undergoing ART, and 21% (n = 221) dropped out of the MAR process without a live birth. Satisfaction rates regarding the received medical care were above 80%, but 42% of patients pointed out the lack of information about non-medical support. An important impact on sexual life was reported, with 21% of patients admitted having not had intercourse for several weeks or even several months. Concerning the impact on professional life, 63% of active workers currently in an MAR program (n = 185) considered that MAR had strong repercussions on the organization of their working life with 49% of them reporting a negative impact on the quality of their work, and 46% of them reporting the necessity to lie about missing work during their treatment. Conclusion: Despite a high overall level of satisfaction regarding medical care, the burden of infertility and MAR on quality of life is strong, especially on sexuality and professional organization. Clinical staff should be encouraged to develop non-medical support for all patients at any stage of infertility treatment. Enterprises should be warned about the professional impact of infertility and MAR to help their employees reconcile personal and professional life.
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Abstract We consider an overlapping generations economy in which agents differ through their ability to procreate. Ex‐ante infertile households may incur health expenditure to increase their chances of parenthood. This health heterogeneity generates welfare inequalities that deserve to be ruled out. We explore three different criteria of social evaluation in the long‐run: the utilitarian approach, the ex‐ante egalitarian criterion and the ex‐post egalitarian one. We propose a set of economic instruments to decentralize each solution. To correct for the externalities and health inequalities, both a preventive (a taxation of capital) and a redistributive policy are required. We show that a more egalitarian allocation is associated with higher productive investment but reduced health expenditure and thus, lower population growth.
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Abstract We show that a monopolist's profit is higher if he refrains from collecting coarse information on his customers, sticking to constant uniform pricing rather than recognizing customers' segments through their purchase history. In the Markov perfect equilibrium with coarse information collection, after each commitment period, a new introductory price is offered to attract new customers, creating a new market segment for price discrimination. Eventually, the whole market is covered. Shortening the commitment period results in lower profits. These results sharply differ from the ones obtained when the firm can uncover the exact willingness-to-pay of each previous customer.
Keywords Price-discrimination
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Abstract Purpose To address the gap highlighted in the literature on the effect of professional interventions to facilitate continued employment, this study aims to evaluate the effect of workplace accommodations on the continued employment 5 years after a cancer diagnosis. Methods This study is based on VICAN5, a French survey conducted in 2015-2016 to examine the living conditions of cancer survivors 5 years after diagnosis. Two subsamples, one with and one without workplace accommodations, were matched using a propensity score to control for the individual, professional, and medical characteristics potentially associated with receipt of workplace accommodations. Results The study sample was composed of 1514 cancer survivors aged 18-54 and employed as salaried at diagnosis. Among them, 61.2% received workplace accommodations within 5 years after diagnosis: 35.5% received a modified workstation, 41.5% received a modified schedule, and 49.2% received reduced hours. After matching, receipt of workplace accommodations appeared to improve the continued employment rate 5 years after cancer diagnosis from 77.8% to 95.0%. Conclusions Receipt of workplace accommodations strongly increases the continued employment of cancer survivors 5 years after diagnosis. More research is needed to better understand the differences in receipt of workplace accommodations along with the related selection effect.
Keywords France, VICAN5, Continued employment, Workplace accommodations, Cancer survivors
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Abstract We specify unconventional monetary policy reaction functions for the Fed using linear and nonlinear econometric frameworks. We find that nonstandard policy measures are largely driven by the dynamics of inflation and the output gap, with the effect being particularly strong during QE rounds. Moreover, we uncover the presence of asymmetry and regime dependence in central bank’s actions since the global financial crisis, especially concerning the response of the term spread and the shadow short rate to the growth rate of central bank reserves. From a policy perspective and given the lack of a systematic response of monetary policy to asset price growth in nonstandard times, our findings seem to corroborate the view that concerns about asset price bubbles, financial sector pro-cyclicality and systemic risk should be part of the macro-prudential policy toolkit.
Keywords Unconventional monetary policy reaction function, Term spread, Shadow short rate, Output gap, Inflation, Nonlinear models, Asset prices, Central bank reserves
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Abstract We investigate empirically, and explain theoretically, how the relative wages of skilled and unskilled workers vary with their relative supplies in open economies. Our results combine the insights of simple labour market and trade models. In countries that trade, relative wages respond inversely to variation in skill supplies, but the response decreases with the degree of openness to trade and is small in very open countries. To reconcile our results with standard estimates of the elasticity of substitution between skilled and unskilled workers, we allow also for the influence of directed technical change and income elasticity of demand for skill-intensive goods.
Keywords Wage inequality Labour markets Heckscher–Ohlin Trade and wages Directed technical change
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