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Sahel fuel smuggling and terrorist taxation: How ECOWAS subsidy reform created a Jihadist revenue haven along the Niger–Nigeria border (Magaria–Jibia Axis)
No full textAfter the ECOWAS-backed abolition of Nigeria’s premium-motor-spirit (PMS) subsidy in June 2023, the pump-price gap between Nigeria and Niger widened overnight from 0.23 to 0.71 USD litre⁻¹. Using a difference-in-differences design that exploits (i) 400+ border checkpoints (Clingendael 2022 GIS), (ii) 13 241 ACLED road-block events 2020-24, and (iii) monthly NBS price panels 2010-24, we show that jihadist taxation revenue on the Magaria–Jibia corridor increased by 0.9–1.4 USD million per month (≈ 18 % of IS-Sahel’s estimated budget). A structural gravity model calibrated to OECD-SWAC trade elasticities implies that a 0.10 USD litre⁻¹ price gap raises the probability of an Islamist checkpoint by 6.3% (SE 1.7, p<0.01) in PPML and 8.9 % (SE 2.4, p<0.01) in IV-2SLS, the latter implying an upper-bound revenue gain of USD 1.4 million per month. A partial-equilibrium counter-factual indicates that reinstating a targeted 0.30 USD litre⁻¹ “border-zone subsidy” would cost Abuja 54M USD yr⁻¹ but deprive insurgents of 11M USD yr⁻¹— a 5:1 cost-denial ratio. We provide the first quasi-experimental evidence that a commodity-price shock directly increases terrorist tax revenue, and show that a temporary border-zone subsidy can claw back 80 % of this income at one-fifth the cost of military surges
Election and Subjective Well-Being: Evidence from the 2024 U.S. Presidential Election
No full textThis paper uses daily Behavioral Risk Factor Surveillance System data to estimate the causal effect of the 2024 U.S. presidential election, a highly competitive race whose outcome resolved lingering uncertainty on election day, on mental-health and life-satisfaction outcomes through a regression discontinuity design. Following the resolution of electoral uncertainty on election day, we find a sharp and persistent post-election decline in subjective well-being, concentrated among female, non-White, urban, and more-educated respondents. These findings reveal an expected-outcome shock, showing that political polarization itself, not electoral surprise, can act as a chronic psychological stressor
0.001% and Counting: Revisiting the Price Rounding Tax
No full textIn 1991 and 2008, Israel abolished the equivalents of 1¢ and 5¢ coins, respectively, effectively eliminating low-denomination coins and introducing rounding in cash transactions. When totals were rounded up, shoppers incurred a small rounding tax. Using detailed data on price endings and basket sizes across supermarkets, drugstores, small groceries, and convenience stores, we estimate that the magnitude of the rounding tax borne by Israeli consumers averaged only 0.001%–0.002% of revenues in the fast-moving consumer goods markets. These findings have implications for the ongoing debate regarding the desirability and viability of abolishing the 1¢ and 5¢ coins in the US
Total Factor Productivity of Manufacturing Firms: Pakistan, 2022 Scenario
No full textTotal Factor Productivity (TFP) represents the efficiency with which capital and labor inputs are utilized in the production process. It captures the impact of elements beyond mere increases in the quantity of inputs and represents factors such as technological progress, innovation, improvements in organizational efficiency and institutional quality.
This study estimates TFP of manufacturing firms in Pakistan using latest available firm level data collected and compiled for the World Bank Enterprise Survey (WBES) of 2022. Data of the WBES of 2007 is also employed to estimate comparative TFP magnitudes. The research also evaluates the impact of few organizational characteristics of firms on the current level of TFP for the year 2022.
The study indicates low level of TFP with the deteriorating trend. These results are consistent with the findings of earlier research on TFP in the context of Pakistan. This study estimates close to 9 percent decline in the magnitude of TFP during the period of 2007 and 2022. However, the extent of deterioration varies across provinces and across industrial sectors. The largest decline (25 percent) in TFP magnitude is estimated in Baluchistan province, followed by KPK (10%). In terms of industrial sectors, the notable sectors where TFP magnitude has declined are Food (43%) and Leather and Leather product (45%). In contrast, sectors in which TFP has improved during 2007-2022 include; Machinery and Equipment (56%), Chemical and Chemical Products (47%) and Wearing Apparels (27%).
The econometrical results related with the determinants of productivity suggest that factors which enhance the firms’ performance and level of productivity include; use of information and communication technology, formal training programs for employees, access to international market, proportion of skilled production workers and the presence of competitive market environment.
The TFP literature suggests that to increase TFP in Pakistani manufacturing firms, a multifaceted approach focused on improving efficiency, technology, human capital, and the overall business environment is required
Aggregating Trade Shocks: From Local Labor Markets to National Outcomes
No full textWe leverage a novel spatial IV approach to develop a reduced-form estimator that maps local trade shocks into aggregate outcomes, accounting for inter-regional spillovers. For the China shock in the U.S., we find strong evidence for employment spillovers at the local level, which appear to propagate through input-output linkages rather than labor mobility. They shift the shock’s employment ramifications away from the Pacific and North Atlantic towards the South Atlantic region. For aggregate employment, our model rationalizes the 30% difference between Autor et al. (2013) and the structural follow-up literature but implies that it is insignificant from a statistical standpoint
A Unified Axiomatic Theory of Microeconomics: Market Structure and Equilibrium
No full textWe propose a unified microeconomic theory that takes the behavioral rules of firms in real markets as the endogenous mechanism through which market structures are generated, replacing the standard practice of imposing perfect competition, monopoly, and other market forms as exogenous assumptions. Under a set of minimal axioms (consumer utility maximization, firm profit maximization, firm entry/exit mechanisms, and market clearing) and by introducing realistic cost and demand structures (firm-level cost heterogeneity, fixed costs, and demand elasticity, among others), pricing behavior and market structures long treated as exogenous (such as perfect competition and monopoly) are derived endogenously as equilibrium outcomes of firms' profit-maximizing behavior. Within a single framework, the theory nests traditional cost and marginal analysis, game-theoretic approaches to imperfect competition, and the Walrasian general equilibrium model; different regions of the parameter space naturally yield equilibrium outcomes corresponding to perfect competition, monopoly, monopolistic competition, and competitive-fringe structures. Our analysis shows that perfect competition is only a highly symmetric and intrinsically unstable equilibrium point: even small cost differences suffice to push the system toward more common monopoly or oligopoly configurations, while positive feedback mechanisms render these structures stable, helping to explain why market power is not easily competed away. Under empirically observable premises, the theory coherently derives the principal market forms and, in doing so, clarifies the domains of applicability of various classic models. It can also be used to predict which market structures industries will evolve toward under given conditions, providing a unified and operational theoretical foundation for empirical research, industrial policy, and firms' business and competitive strategy decision-making
Tracking Public Interest in Sustainable Mobility with Google Trends
No full textThe transport sector remains one of the main contributors to global GHG emissions, making the shift toward more sustainable mobility a key component of climate-mitigation strategies. While previous research has emphasized the role of infrastructure, technology, and behavioral change, less is known about how public attention toward sustainable transport evolves and diffuses across countries. This paper uses Google Trends data as a high-frequency indicator of public interest in sustainable mobility for 38 OECD countries from 2004 to 2025. To ensure comparability across time and space, we propose the construction of log-ratios between sustainable mobility and conventional car-related searches so that the measure is robust to changes in Google’s user base. We apply the Phillips and Sul convergence framework to test whether attention levels follow common long-run trajectories. Results show strong convergence in electric-vehicle attention, while hybrid- and public-transport interest remain fragmented. Validation analyses confirm that Google Trends indicators correlate with subsequent electric-vehicle adoption, underscoring their value as dynamic proxies for cultural and behavioral dimensions of sustainable mobility
Polynomial-Time Algorithms for Computing the Nucleolus: An Assessment
No full textRecently, Maggiorano et al. (2025) claimed that they have developed a strongly polynomial-time combinatorial algorithm for the nucleolus in convex games that is based on the reduced game approach and submodular function minimization method. Thereby, avoiding the ellipsoid method with its negative side effects in numerical computation completely. However, we shall argue that this is a fallacy based on an incorrect application of the Davis/Maschler reduced game property (RGP). Ignoring the fact that despite the pre-nucleolus, other solutions like the core, pre-kernel, and semi-reactive pre-bargaining set possess this property as well. This causes a severe selection issue, leading to the failure to compute the nucleolus of convex games using the reduced games approach. In order to assess this finding in its context, the ellipsoid method of Faigle et al. (2001) and the Fenchel-Moreau conjugation-based approach from convex analysis of Meinhardt (2013) to compute a pre-kernel element were resumed. In the latter case, it was exploited that for TU games with a single-valued pre-kernel, both solution concepts coincide. Implying that one has computed the pre-nucleolus if one has found the sole pre-kernel element of the game. Though it is a specialized and highly optimized algorithm for the pre-kernel, it assures runtime complexity of O(n^3) for computing the pre-nucleolus whenever the pre-kernel is a single point, which indicates a polynomial-time algorithm for this class of games
Assessing the safe haven characteristic of Sukuk in Iran's financial market: Fresh evidence for portfolio management
No full textThis paper examines the spillover effects between Sukuk and key alternative assets- conventional stock, gold, and currency- in Iran from July 2013 to December 2024. Using three advanced models-Quantile-on-Quantile (Gabauer & Stenfors, 2024), the contemporaneous and lagged R2 decomposed connectedness (Balli et al., 2023), and a portfolio approach (Broadstock et al., 2022)-the study finds that Iran's Sukuk market lacks depth for hedging against gold, currency, and stock risks across direct and reverse quantiles and under various shocks. Results show that the USD is the main contemporaneous driver, while Sukuk is a net receiver in average and contemporaneous connections. Sukuk also offers low long-term returns, making it less competitive. Gold proves optimal for long-term investment, mainly when currency acts short-term. Currency is the primary source of short-term volatility, but Sukuk fails as a stabilizing tool. Thus, including Sukuk in portfolios does not enhance diversification for risk-averse investors during crises due to its limited hedging ability in Iran
Belgian start-ups in Artificial Intelligence
No full textWe attempt to map out as comprehensively as possible the Belgian companies that offer goods or services with an AI component. The 744 Belgian AI start-ups that we identified (founded since 2010) appear, in comparison with non-AI start-ups, to focus primarily on revenue growth, which is often accompanied by a sharp increase in the number of employees. On the other hand, many of the AI start-ups are not yet profitable, especially those with venture capital. AI start-ups without venture capital are
overrepresented in the very small group of the most successful Belgian start-ups, which have high turnover, many employees and are very profitable