M. Di Maio, V. Leone Sciabolazza (2023), Conflict exposure and labour market outcomes: Evidence from longitudinal data from the Gaza Strip, Labour Economics, 85, 102439

This paper documents the effect of variations in the individual-level intensity of conflict exposure on various labour market outcomes for Palestinians living in the Gaza Strip. Combining individual-level longitudinal employment data and geolocalised information on conflict-related events, we show that an increase in conflict exposure of the individual, while it does not affect the employment status on average, it has a heterogeneous impact on job transitions depending on the worker being employed in the private or the public sector. We also find that, for those in the private sector, higher conflict exposure reduces the labour income and the number of hours worked. For those in the public sector, the effect of conflict is instead null on both the labour income and the number of hours worked and it is positive on wages. Finally, we provide suggestive evidence that these results are explained by the combination of two mechanisms, namely the conflict-induced change in the health conditions of the workers (which affects the labour supply) and in the level of the local economic activity (which affects the labour demand).


L. Forastiere, D. Del Prete, V. Leone Sciabolazza (2024), Causal Inference on Networks under Continuous Treatment Interference: an application to trade distortions in agricultural markets, Social Networks, 76, 88-111

This paper investigates the case of interference, when a unit’s treatment also affects other units’ outcome. When interference is at work, policy evaluation mostly relies on the use of randomized experiments under cluster interference and binary treatment. Instead, we consider a non-experimental setting under continuous treatment and network interference. In particular, we define spillover effects by specifying the exposure to network treatment as a weighted average of the treatment received by units connected through physical, social or economic interactions. Building on Forastiere et al. (2021), we provide a generalized propensity score-based estimator to estimate both direct and spillover effects of a continuous treatment. Our estimator also allows to consider asymmetric network connections characterized by heterogeneous intensities. To showcase this methodology, we investigate whether and how spillover effects shape the optimal level of policy interventions in agricultural markets. Our results show that, in this context, neglecting interference may underestimate the degree of policy effectiveness.

Download paper (PDF)

M. Di Maio, N. Elmallakh, V. Leone Sciabolazza, News and migration decisions: Evidence from Libya.

This paper examines the impact of the politicized framing of migration in the news on migration choices in Libya, the most important gateway to Europe. Relying on broadcast, print, and web news on migration in destination countries, as well as on geo-localized panel data on registered migrants in Libya, we find that a worsening of the tone of migration-related news in destination countries is associated with an increase in the length of stay of migrants in Libya. Interestingly, we find that migrants are more sensitive to a worsening in the tone of positive news (pro-immigration discourse) but not to the tone of negative news (anti-immigration discourse). Our results also support the underlying mechanism of news consumption among migrants and seem to be driven by areas with higher Internet coverage, as proxied by the intensity of night lights.

M. Battaglini, V. Leone Sciabolazza, Lin M., E. Patacchini, Money, Influence (and Death) in U.S. Politics.

It has long been observed that there is little money in U.S. politics, at
least compared to the stakes. This has led researchers to question whether
contributions are instrumental political investments since, in this case, we
would see more of them. But what if contributions are not fully observable
or non-monetary in nature? Can large donors gain sway over candidates
even with small contributions? We address this question with a new data
set on the top 1000 donors in U.S. congressional races. We do not focus
on what they give (which indeed may be unobservable), but on what they
accomplish. Since top donors do not randomly support candidates, we
base our identification strategy on information about top donors’ deaths
and the observed variations in candidates’ performance after these events.
We document that, on average, the death of a top donor decreases a
candidate’s likelihood of being elected by 3%. Candidates’ outcomes are
not simply affected by the decrease in their monetary contributions, but
also by the prominence of the deceased donor: Candidates losing the most
influential top donors (as measured by Google searches of their names and
other measures) are those who suffer the most.

M. Di Maio, F. Fasani, V. Leone Sciabolazza, V. Molini (2023), Facing Displacement and a Global Pandemic: Evidence from a Fragile State, Journal of Demographic Economics, 1-26. Previous version: CEPR discussion paper, DP17104

We use novel survey data to assess the impact of COVID-19 pandemic on the Libyan population. In our sample, 9.5% of respondents report that a household member has been infected by COVID-19, while 24.7% of them have suffered economic damages and 14.6% have experienced negative health effects due to the pandemic. Our analysis focuses on the differences between IDPs and non-displaced individuals, controlling for individuals and household characteristics, geo-localized measures of economic activity and conflict intensity. Displaced individuals do not experience higher incidence of COVID-19 relative to comparable non-displaced individuals, but are about 60% more likely than non-displaced respondents to report negative economic and health impacts caused by the pandemic. Our results suggest that the larger damages suffered by IDPs can be explained by their weaker economic status – which leads to more food insecurity and indebtedness – and by the discrimination they face in accessing health care.


M. Battaglini, V. Leone Sciabolazza, E. Patacchini (2023), Abstentions and Social Networks in Congress, The Journal of Politics, forthcoming. Previous version: NBER Working Paper 27822

We study the extent to which personal connections among legislators influence abstentions in the U.S. Congress. Our analysis is conducted by observing representatives’ abstention for the universe of roll call votes held on bills in the 109th-113th Congresses. Our results show that a legislator’s propensity to abstain increases when the majority of his or her alumni connections abstains, even after controlling for other well-known predictors of abstention choices and a vast set of fixed effects. We further reveal that a legislator is more prone to abstain than to take sides when the demands from personal connections conflict with those of the legislator’s party.

Download PDF

Battaglini M., Leone Sciabolazza V., Patacchini E., Logrolling in Congress, NBER Working Paper 31169. R&R Journal of Law, Economics, and Organization.

We study vote trading among U.S. Congress members. By tracking roll-call votes within bills across five legislatures and politicians’ personal connections made during the school years, we document a propensity of connected legislators to vote together that depends on how salient the bill is to the politicians’ legislative agenda. Although this activity does not seem to enhance U.S. Congress members’ legislative effectiveness, vote trading is a strong predictor of future promotions to position of leadership.


M. Di Maio , V. Leone Sciabolazza , V. Molini (2023), Migration in Libya: a spatial network analysis, World Development, 163, 106139. Previous version: World Bank, Policy Research Working Paper 9110

This paper provides the first systematic analysis of migration to, within, and from Libya. The data used in the analysis are from the Displacement Tracking Matrix data set of the International Organization for Migration. The analysis uses this unique source of data, combining several techniques to analyze various dimensions of migration in Libya. First, the paper provides a detailed description of the demographic characteristics and national composition of the migrant populations in Libya. Next, it discusses the determinants of migration flow within Libya. The findings show that migration in Libya can be characterized as forced migration, because conflict intensity is the main determinant of the decision to relocate across provinces. Finally, the paper describes the direction, composition, and evolution of international migration flows passing through Libya and identifies the mechanisms of location selection by migrants within Libya by identifying hotspots and cluster provinces.

Download paper (PDF)

M. Fontana, M. Iori, V. Leone Sciabolazza, D. F. De Souza (2022), The interdisciplinarity dilemma: public versus private interests, Research Policy, 51(7), 104553

Researchers often receive contrasting incentives when conducting their work. On the one hand, an interdisciplinary approach is required to produce scientific advances and access to funding. On the other, academic scholarships and evaluation mechanisms are still organized following the criteria of traditional disciplinary fields. If pursuing interdisciplinary research results in contrasting outcomes, science may face an interdisciplinarity dilemma: should researcher pursue their own private interest to build a reputation? Or should they endeavor towards public interest? How costly in terms of reputation is to choose interdisciplinarity research (IDR) over (more) specialized research?
We answer these questions by exploiting data on 23,926 articles published by 6,105 researchers affiliated with the University of Florida in the period 2008-2013. Through individual fixed-effect, we compare articles of the same scholar to roll out the influence of individual characteristics on the scientific impact of their research.
We find that the diverse dimensions of IDR (Variety, Balance, and Disparity) have a different effect on the reputation of a scholar and on her contribution to societal research. We confirm the existence of trade-off between private and public interest. We also point out that the increase of IDR aiming at connecting distant disciplines reduces the usefulness of the resulting knowledge. Results are robust to various specifications and apply to all scholars, regardless of their gender, collaboration behavior, discipline, and performance. These findings pose challenging questions to policymakers.

Link to pdf

M. Battaglini, V. Leone Sciabolazza, E. Patacchini, S. Peng (2022), An R Package for the Estimation of Parameter-Dependent Network Centrality Measures, Journal of Statistical Software, 102(8), 1-30.

The R package econet provides methods for estimating parameter-dependent network centrality measures with linear-in-means models. Both nonlinear least squares and maximum likelihood estimators are implemented. The methods allow for both link and node heterogeneity in network effects, endogenous network formation and the presence of unconnected nodes. The routines also compare the explanatory power of parameter-dependent network centrality measures with those of standard measures of network centrality. Benefits and features of the econet package are illustrated using data from Battaglini and Patacchini (2018), which examine the determinants of US campaign contributions when legislators care about the behavior of other legislators to whom they are socially connected.

Download Paper (PDF)
Download Software (Link)