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- Facility-level estimates of demand for industrial process heat in CaliforniaPublication . Saad, Dimitri M.; Brandt, Adam R.; Azevedo, Inês M. L.; NOVA School of Business and Economics (NOVA SBE); IOP PublishingThe industrial sector in the U.S, contributes to 23% of the nation’s annual emissions from the combustion of fossil fuels, generated for process heat end-use, and process emissions, produced as a byproduct of industrial processes. The demand for industrial process heat is not well quantified, as it varies across industries, processes, fluid media (steam/combustion gases), temperature requirements, and over time. Decisions regarding future technologies, processes, and fuels that can meet industrial heat demand in an economically viable manner while minimizing the environmental and social negative consequences associated with industrial heat require such information. In this work, we develop a method to estimate heat demand for industrial facilities and apply it to 120 facilities (representing 39 manufacturing industries) in California. We find that 27 out of 46 million metric tons of CO2 emitted by California’s manufacturing industries originate from the production of heat. Petroleum refining and oil/gas extraction sites account for 72% of these emissions. Over 85% of California’s industrial heat demand requires temperatures below 600 ◦C, thus holding some potential for electrification.
- Large-dimensional cointegrated threshold factor modelsPublication . Abreu, Daniel; Rodrigues, Paulo M.M.; NOVA School of Business and Economics (NOVA SBE); Blackwell Publishing LtdIn this paper we extend the two-level factor model to account for cointegration between group-specific factors in large datasets. We propose two nonlinear specifications: (i) a threshold vector error correction model (VECM) that allows for asymmetric adjustment across regimes; and (ii) a band VECM that captures state-dependent adjustment which becomes active only when deviations from equilibrium exceed an inaction threshold. Monte Carlo simulations show that the proposed estimators perform well in finite samples, accurately recovering the cointegration relationship and the regime-dependent adjustment mechanism in the designs considered. In an empirical application, we estimate a band factor VECM on a panel of government bond yields from multiple countries, extracting one global factor and two group-specific factors associated with long- and short-term maturities. The results provide evidence of discontinuous adjustment in the global term structure of interest rates, with stronger error correction during periods of larger deviations from the long-run equilibrium.
- Export promotion with matchmaking and grantsPublication . Barbosa, Paulo Henrique; Amador, João; Arranhado, Esmeralda; NOVA School of Business and Economics (NOVA SBE); Wiley-BlackwellThis paper evaluates two core export-promotion tools: internationalization grants and matchmaking services provided by the Portuguese export promotion agency (AICEP). We merge administrative records with customs and firm data for 2012–2021. We employ an event-study approach with firm and year fixed effects in a setup of staggered adoption of the programs. Internationalization grants increase treated firms' total exports by approximately 13%, while matchmaking services raise exports to France by approximately 32%. Effects are larger for micro and small firms (grants 18%; matchmaking 40%) and concentrated in traditional manufacturing sectors. Results also show that both export promotion programs are effective when supporting firms with a permanent presence in international markets, versus occasional exporters. Event-study diagnostics show flat pre-trends, and placebo and anticipation checks support identification. Complementarily, finite-duration robustness tests show no rapid fadeout after 3 years, and a simple cost–benefit analysis indicates that both programs have favorable cost–benefit outcomes.
- Learning about unknowable toolsPublication . da Silva, Ricardo Coelho; Rüling, Charles-Clemens; Duymedjian, Raffi; Zejnilovic, Leid; NOVA School of Business and Economics (NOVA SBE); Elsevier Science B.V., Amsterdam.Generative AI tools are unknowable, because their opacity, probabilistic outputs, and instability prevent knowing why specific outputs are produced, posing challenges for learning in communities of practice. This hinders expertise development and the creation of stable knowledge artifacts. We conducted a netnographic study of interactions in the OpenAI Developer Forum following the release of DALL-E 3 to investigate how communities of practice adapt to an unknowable tool. We find community participants remained in a state of “permanent experimentation”, enabling learning despite the absence of stable expertise. They deployed collective bricolage by gathering, sharing, and recombining examples to navigate the tool's unknowability. We contribute to communities of practice literature by showing collective learning is possible without stable expertise and extend bricolage research by positioning it as an epistemic practice suited to unknowable tools. These insights have implications for understanding learning and innovation in the context of fast-moving, opaque technologies.
- The role of legislation, policy and regulation in estuarine managementPublication . Afonso, Fernando; Fernandes, Miguel; Austen, M. Clare; Broszeit, Stefanie; Brito, Ana C.; NOVA School of Business and Economics (NOVA SBE); ElsevierEstuaries are increasingly populated due to urbanisation, leading to shoreline alteration, and increase of waste discharge and water extraction. Managing an estuary involves taking into consideration the governance framework, which includes a set of policies and legislation at the international and country level. However, current governance systems do not reflect this which limits their ability to manage competing interests, such as tourism, shipping and conservation. Economic activity often drives estuary governance, but continuous loss of biodiversity and habitats highlights the need for more inclusive governance systems that preserve both, natural and socio-economic capital. Reviewing current governance systems can identify challenges and promote solutions. This study reviews the legislation applied to estuarine systems from an international to a regional scale, using Portugal as a reference case. A ‘horrendogram’ was created to assess legislation which was categorised by the following topics: biodiversity, land planning, water management, marine governance, aquaculture and fisheries, waste management, economic policy, forest management, and climate change. Key challenges include limited coordination between maritime and land planning systems, difficulties in incorporating EU legislation into national frameworks, and fragmented administrative responsibilities. To improve estuarine governance, this study recommends enhancing coordination between administrative bodies, promoting stakeholder engagement throughout decision-making processes, and adopting ecosystem service-based approaches. This approach aligns with the sustainability goals by supporting ecosystem health, enhancing human well-being and promoting sustainable economic growth. The insights developed are applicable to estuarine systems globally, and future research should focus on testing governance systems that integrate ecological, social and economic priorities, while promoting collaboration across administrative bodies and stakeholders.
- Closing equity gaps in first-year mathematics through structured interventionPublication . Quintino, Áurea; Xufre, Patrícia; NOVA School of Business and Economics (NOVA SBE); Taylor & FrancisMany students enter their first university-level mathematics course feeling unprepared and overwhelmed. While some arrive with a strong foundation from the national curriculum, others, especially international students or those from alternative academic paths, face a different reality. The gap in mathematical background can quickly lead to confusion, discouragement and a sense of exclusion. To help bridge this gap, we introduced a set of structured, low-stakes support measures. All first-year students began the term with a short diagnostic test. Those who struggled were invited to complete ten focused learning modules designed to reinforce core skills, each comprising two self-assessment quiz attempts. Analysis of data from 258 students showed that those who completed the modules exhibited greater variability in final course grades, reflecting a wider dispersion of outcomes compared to students who met the diagnostic threshold. Despite this variability, a weak but statistically significant positive correlation was observed between quiz engagement and final examination performance, suggesting that structured, repeated practice can support academic improvement. We also saw significant performance variation across student groups, highlighting the value of tailored interventions. Our findings suggest that early diagnostic assessment combined with structured learning support can help transform a difficult start into a pathway toward success.
- The Carnation Revolution and economic crisisPublication . Amaral, Luciano; Marques, Bruno Lopes; Pereira dos Santos, João; NOVA School of Business and Economics (NOVA SBE); Elsevier Science Publisher B.V.On 25 April 1974, the “Carnation Revolution” toppled Western Europe's oldest dictatorship, Portugal's Estado Novo. Political instability ensued, leading to a wage explosion, expropriations, and the collapse of an empire that brought back half a million repatriates. As a result, the Portuguese economy slowed from the high growth it had experienced in the 1950s and ’60s. However, disentangling the effects of the revolution from those of the broader international crisis of the 1970s is challenging. To address this, we apply the synthetic control method and find that the Carnation Revolution, along with the ensuing instability, caused a negative structural break that persistently reduced GDP per capita. By 1976, GDP per capita was almost 15% lower than the counterfactual estimate. This coincided with a decline in the investment-to-employment ratio and higher current account deficits than those observed in comparable countries.
- Serial entrepreneurs and the macroeconomyPublication . De Vera, Micole; Félix, Sónia; Karmakar, Sudipto; Sedláček, Petr; NOVA School of Business and Economics (NOVA SBE); Springer VerlagEntrepreneurship is crucial for job creation and economic growth. But not all entrepreneurs are alike. For instance, firms of serial entrepreneurs — owners of multiple businesses — have been documented to outperform other businesses. In this paper, we provide novel evidence showing that firms of serial entrepreneurs are also important for macroeconomic outcomes. Using unique administrative data from Portugal, we document that serial entrepreneur firms (i) disproportionately contribute to aggregate job creation and productivity growth, (ii) help shape aggregate business dynamism, and (iii) are more likely to be high-growth (“gazelles”). This superior performance is largely driven by entrepreneurs’ education, ability, past managerial experience, and lower indebtedness of their firms. We discuss the implications of our findings for macroeconomic models — which typically ignore serial entrepreneurs.
- Determinants of catastrophic healthcare spending in Portugal (2005–2022)Publication . Tao, Tzi Kieu; Barros, Pedro Pita; NOVA School of Business and Economics (NOVA SBE); Elsevier Science Publisher B.V.The study analyses the extent, evolution and impoverishing effects of catastrophic health expenditures (CHE) in Portugal from 2005 to 2022. The analysis also identifies factors associated with the occurrence of CHE. The results show a progressive reduction in financial burden with increased access to healthcare services. CHE incidence decreased from 9.42% (2005) to 5.04% (2022). Reduced access to the Portuguese NHS was associated to increased reliance on private services and out-of-pocket costs. Barriers, unmet needs and challenges regarding the protection of vulnerable groups remain, including the elderly and individuals incapacitated to work. Households with at least one senior show a particular vulnerability to CHE. Regional disparities are reinforced by underdeveloped healthcare infrastructure, limited access and financial barriers.
- Corrigendum to ‘The Costs of Corporate Debt Overhang’Publication . Blickle, Kristian; Santos, João A.C.; NOVA School of Business and Economics (NOVA SBE); ElsevierWe seek to clarify the handling of the editorial process for the above-referenced article. It was handled solely by Guest Editor Professor Franklin Allen with the support of Managing Editor Professor Murillo Campello. The paper, like the other papers in this special issue, was subject to the Journal's usual independent peer review procedures and standards. DOI of original article: < 10.1016/j.jfi.2024.101118>