My Research

Discussion papers


Peer-reviewed journals

This study investigates the impact of economic incentives on travel-related physical activity, leveraging the London Congestion Charge’s disincentivising of sedentary travel modes via increasing the cost of private car use within Central London. The scheme imposes charges on most types of cars entering, exiting, and operating within the Central London area, while individuals living inside the charging zone are eligible for a 90% reduction in congestion charges. Geographical location information provides the full-digit postcode data necessary to precisely identify the eligibility for the discount of participants in the London Travel Demand Survey for the period 2005–2011. Using a boundary regression-discontinuity design reveals a statistically significantly positive impact on active commuting (i.e. cycling and walking) around the border of the charging zone. The effect is larger for lower-income households and car owners. The findings are robust against multiple specifications and validation tests.


In this paper, we estimate the causal effects of the 2003 reforms to the Italian apprenticeship contract, which increased its legal length, allowed on-the-job training and introduced a minimum floor to apprentices’ wages. Using administrative data, we implement a covariate balancing propensity score and a difference-in-differences estimator. We find that the new contract improves the chances of an apprentice obtaining a permanent job in the same firm five years after hiring; however, this occurs more frequently in large firms. We also find sizeable, long-run wage effects which extend well beyond the legal duration of the apprenticeship contract. These effects are compatible with increased human capital accumulation, possibly due to the reform’s training provisions. 


We study how unemployment benefit eligibility affects the layoff exit rate by exploiting quasi-experimental variation in eligibility rules in Italy. By using a difference-in-differences estimator, we find an instantaneous increase of about 12% in the layoff probability when unemployment benefit eligibility is attained, which persists for at least 16 weeks. These findings are robust to different identifying assumptions and are mostly driven by jobs started after the onset of the Great Recession and in the South.


We investigate the role of temporary contracts in shaping wage inequality in a dual labour market. Based on Italian individual-level administrative data, our analysis focuses on new hires in temporary and open-ended contracts for the period of 2005-2015. To estimate the presence of differentials over the daily wage distribution, we follow Firpo (2007) and implement an inverse probability estimator, which allows us to control for labour market history, including lagged outcomes, over the last 16 years. Our results show the existence of a premium for temporary contracts over the full distribution of daily remuneration at entry, confirming the economic theory of equalizing differences. The wage premium is greater when permanent contracts are more valuable, such as for `marginalised' categories like female, young, and low-paid temporary workers, and during the years of the economic crisis. The gap remains substantial after taking into account differences in working hours between workers.


In this paper we study the effects on the survival rate in employment of a scheme that facilitates gradual retirement through working time reductions. We use information on the entire labour market career and other observables to control for selection and take dynamic treatment assignment into account. We also estimate a competing risks model considering different (possibly selective) pathways to early retirement. We find that participation in the scheme prolongs employment during the first two (four) years for men (women). However, when individuals become eligible for early retirement the effect reverses. This suggests that time credit initially improves the work-life balance, but that it eventually decreases labour market attachment and signals to employers a preference for early retirement. The institutional environment in which part-time participants are entitled to full-time pensions reinforces the latter process. Participation in time credit seems also to generate a slight, statistically insignificant, improvement in health. 


This paper examines the effects of a permanent wage cost subsidy in Belgium on employment retention, working time and hourly wage of older men. To estimate these effects we propose a semi-parametric weighted difference-in-differences estimator that accounts for endogenous stratification in the sampling from a population of men born between 1941 and 1950. We find small positive short-run impacts on working time and larger ones on the retention rate in employment, but only for employees at high risk of early retirement. The wage is not affected. Keywords: Wage cost subsidies, older workers, weighted difference-in-differences, endogenous sampling.


We test whether ethnic discrimination is heterogeneous by job candidates’ work experience. Fictitious applications are sent to vacancies. We find significant discrimination when candidates have no or little experience but no unequal treatment when they have twenty years of experience. Keywords: Hiring discrimination; Statistical discrimination; Ethnicity; Experience; Human capital.




Publications outside Economics

Accelerating efforts for the Sustainable Development Goals requires understanding their synergies and trade-offs at the national and sub-national levels, which will help identify the key hurdles and opportunities to prioritize them in an indivisible manner for a country. Here, we present the importance of the 17 goals through synergy and trade-off networks. Our results reveal that 19 provinces show the highest trade-offs in SDG13 (Combating Climate Change) or SDG5 (Gender Equality) consistent with the national level, with other 12 provinces varying. 24 provinces show the highest synergies in SDG1 (No Poverty) or SDG6 (Clean Water and Sanitation) consistent with the national level, with the remaining 7 provinces varying. These common but differentiated SDG priorities reflect that to ensure a coordinated national response, China should pay more attention to the provincial situation, so that provincial governments can formulate more targeted policies in line with their own priorities towards accelerating sustainable development.


Over the first half of March 2021, the majority of European governments suspended Astrazeneca’s Vaxzevria vaccine as a precaution following media reports of rare blood clots. We analyse the impact of the European Medicines Agency’s (EMA) March 18th statement assuring the public of the safety of Vaxzevria and the immediate reinstatement of the vaccine by most countries on respondents’ intention to get vaccinated. By relying on survey data collected in Luxembourg and neighbouring areas between early March and mid-April, we observe that the willingness to be vaccinated was severely declining in the days preceding the EMA statement. We implement a regression discontinuity design exploiting the time at which respondents completed the survey and find that the vaccine reinstatement substantially restored vaccination intentions.


This study is the first to investigate whether the introduction of additional assistant referees in the UEFA Europa League (2009–2010 season) and the UEFA Champions League (2010–2011 season) was associated with lower referee bias in terms of home and “big” team favouritism. To this end, we analyse a unique database with pre- and within-game characteristics of all games in seven recent seasons in these leagues by means of bivariate probit regression models. We find evidence for substantial referee bias before the introduction of additional referees, while no such evidence is found after the introduction. Furthermore, additional assistants go hand in hand with more yellow cards for both home and away teams. We show that these findings are robust to multiple operationalisations of referee bias and that they are not just picking up a general time evolution towards less referee bias or the effect of parallel reforms.


This study is the first to estimate the effects of the sending-off of a player on the full time results in international club soccer. To this end, we analyse data of more than 2,000 recent matches in the UEFA Champions League and UEFA Europa League. We find that when home teams receive a red card, it harms their goal scoring and victory probabilities. By contrast, a red card for away teams can have a positive, negative, or neutral effect for them, depending on the timing of the player dismissal.


Conference proceedings


Ongoing projects


Referee for Academic Journals


Referee for Research Grants