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- Socio-economic sensitivity to weather extremesPublication . Pandit, Dhruv Akshay; Neto, Miguel de Castro; Rodrigues, Paulo M. M.; Information Management Research Center (MagIC) - NOVA Information Management School; NOVA Information Management School (NOVA IMS); NOVA School of Business and Economics (NOVA SBE)While a growing body of research has examined the economic and social consequences of extreme weather, few attempts have been made to collate this evidence into a coherent map. This scoping review addresses this gap by providing the first systematic mapping of research on the socio-economic sensitivity of European regions to short-run weather shocks. Following a PRISMA-ScR protocol, we search Scopus and Web of Science, identifying 77 eligible articles published between 2000 and 2025. We analyse how studies define and measure weather shocks and socio-economic outcomes, the data and methods they employ, the sectors and regions they cover, as well as the associated impacts across sectors and the channels they operate through. Our review finds that weather shocks are consistently associated with reduced output growth, increased heat-related mortality, rising inflationary pressures, and greater inequality, with effects varying by region, sector, and income level. However, we also identify significant gaps in spatial resolution, sectoral coverage, and methodological diversity. By mapping the existing evidence and its limitations, this review provides a structured foundation for future research on weather-related socio-economic risk in Europe.
- Using digital technology to strengthen oversight of public procurement in PortugalPublication . Hlacs, Andras; Wells, Helene; Damásio, Bruno; Vasconcelos, Carolina; Sturm, Niclas Frederic; Gonçalves, Ana; Batista, Pedro; Information Management Research Center (MagIC) - NOVA Information Management School; NOVA Information Management School (NOVA IMS)The digital transformation of oversight and integrity institutions is crucial for enhancing transparency, efficiency, and accountability in the management of public procurement and public funds. Prioritising the digital transformation of institutions responsible for oversight and audit helps these institutions improve service delivery and foster citizen engagement. Oversight and integrity institutions that can integrate advanced digital technologies and analytics, including artificial intelligence (AI), are in a better position to detect, prevent, and address corruption and misconduct. Given the complexity and volume of data that institutions, including supreme audit institutions (SAIs), are required to consider, the adoption of digital tools to streamline processes and to improve data and risk analysis is necessary. The Tribunal de Contas (Court of Auditors, hereafter TdC) is Portugal’s SAI and is responsible for overseeing the proper management and legal use of Portugal’s public resources. It plays a critical role in ensuring the regularity, efficiency and cost-effectiveness of public procurement in Portugal. The OECD and NOVA University Lisbon (Universidade) helped TdC develop and refine a risk assessment methodology, including the development of a data-driven risk model to undertake audit assessments. The initiative aims to improve the TdC’s identification of risks and the early detection of irregularities through advanced data analysis and machine learning (ML), a form of artificial intelligence (AI). The methodology developed marks a significant milestone in the TdC’s digital transformation. The risk indicators include a mixture of rule-based (red flags for simple rule violations, such as no competition in a high-value contract”), inference-based (red flags for patterns or repeated behaviour, such as “the same company always wins”), and model-based (red flags found by smart systems that learn from past data to spot unusual activity) indicators and require access to external data sources. This initiative has been selected as an example to highlight the implementation considerations and challenges (such as data quality) that oversight and integrity institutions must consider when developing a model. Several good practices have been identified during the development of the risk assessment methodology that underline the importance of shared understanding and commitment to addressing these challenges when developing and implementing any data-driven audit risk model. For example, improving the quality and accuracy of data and committing to investing in knowledge sharing and enhancing staff expertise and skills. Collaboration, sharing, and access to data across multiple institutions require stakeholders to be identified early and to be proactively and routinely engaged in the development of an audit risk model. Data custodians need to be involved in the model’s critical appraisal and review. Data-driven audit risk models should not remain static: ongoing enhancements and updates to a model may involve the development and implementation of more advanced indicators of risks. Finally, opportunities for automation and scalability of the data-driven risk assessment and its continuous optimisation (for example, feature engineering or updates to the data pipeline) provide further opportunities to ensure the sustainable implementation
- Sobre a análise em componentes principaisPublication . Rosado, FernandoA análise em componentes principais é uma parte importante no estudo da análise estatística multivariada.
- Automatic Adjustment Mechanisms In Pension SystemsPublication . Bravo, Jorge Miguel; Ayuso, Mercedes; Herce, José A.; Palmer, Edward; Dómenech, Rafael; Information Management Research Center (MagIC) - NOVA Information Management School; NOVA Information Management School (NOVA IMS)In the search for the sustainability of public pension systems, both, gradual parametric reforms (changes in retirement age, contribution rates or revaluation adjustments) and systemic reforms (NDC schemes) have been the main strategies as high-income countries have responded to continuous longevity increases, below replacement level fertility, and the corresponding upward trend in old-age dependency ratios. All this has also happened in low productivity gains and economic growth, rapidly shifting labor markets, changing interest rates and regulatory reforms scenarios.
- A Systematic Literature Review of Peer-to-Peer, Community Self-Consumption, and Transactive Energy Market ModelsPublication . Capper, Timothy; Gorbatcheva, Anna; Mustafa, Mustafa A.; Bahloul, Mohamed; Schwidtal, Jan Marc; Chitchyan, Ruzanna; Andoni, Merlinda; Robu, Valentin; Montakhabi, Mehdi; Scott, Ian; Francis, Christina; Mbavarira, Tanaka; Espana, Juan Manuel; Kiesling, Lynne; Information Management Research Center (MagIC) - NOVA Information Management School; NOVA Information Management School (NOVA IMS)Peer-to-peer and transactive energy markets, and community or collective self-consumption offer new models for trading energy locally. Over the past 10 years there has been significant growth in the amount of academic literature and trial projects examining how these energy trading models might function. This systematic literature review of 139 peer-reviewed journal articles examines the market designs used in these energy trading models. The Business Ecosystem Architecture Modelling framework is used to extract information about the market models used in the literature and identify differences and similarities between the models. This paper identifies six archetypal market designs and three archetypal auction mechanisms used in markets presented in the reviewed literature. It classifies the types of commodities being traded, the benefits of the markets and other features such as the types of grid models. Finally, this paper identifies five evidence gaps which need future research before these markets can be widely adopted.
- Intergenerational Actuarial Fairness When Longevity Increases: Amending the Retirement AgePublication . Bravo, Jorge M.; Ayuso, Mercedes; Holzmann, Robert; Palmer, Edward; Information Management Research Center (MagIC) - NOVA Information Management School; NOVA Information Management School (NOVA IMS)Continuous longevity improvements and population ageing have led countries to modify national public pension schemes by increasing the standard and early retirement ages in a discretionary, scheduled, or automatic way, and by making it harder for people to retire prematurely. To this end, countries have adopted alternative retirement age strategies, but our analyses show that the measures taken are often poorly designed and consequently misaligned with the pension scheme’s ultimate goals. In addition, our analyses demonstrate that countries risk falling short of their goals given their use of projection methods that underestimate life expectancy. This paper discusses how to implement automatic indexation of the retirement age to life expectancy developments while respecting the principles of intergenerational actuarial fairness and neutrality among generations. We show that in policy designs in which extended working lives translate into additional pension entitlements, the pension age must be automatically updated to keep the period in retirement constant. Alternatively, policy designs that pursue a fixed replacement rate are consistent with retirement age policies targeting a constant balance between active years in the workforce and years in retirement. The empirical strategy employed to project the relevant cohort life expectancy uses a Bayesian Model Ensemble approach to stochastic mortality modelling to generate forecasts of intergenerationally and actuarially fair pension ages for 23 countries and regions from 2000 to 2050. The empirical results show that the pension age increases needed to accommodate the effect of longevity developments on pay-as-you-go equilibrium and to reinstate equity between generations are sizeable and well beyond those employed and/or legislated in most countries. A new wave of pension reforms may be at the doorsteps.
- Edad de jubilación y vinculación a la esperanza de vidaPublication . Ayuso, Mercedes; Palmer, Edward; Bravo, Jorge Miguel; Information Management Research Center (MagIC) - NOVA Information Management School; NOVA Information Management School (NOVA IMS)La esperanza de vida se ha convertido probablemente en el indicador biométrico por excelencia a la hora de calcular la edad legal de jubilación en las reformas de pensiones que se están realizando en los distintos países. Sin embargo, la estimación del número esperado de años de vida a partir de la jubilación puede variar significativamente en función del método de cálculo utilizado. Si en trabajos anteriores analizábamos el impacto del gap entre esperanzas de vida calculadas por métodos periodo y cohorte en la equidad intergeneracional (Ayuso, Bravo y Holzmann, 2020) ahora el objetivo es cuantificar el impacto de esta medida en el cálculo de la edad legal de jubilación. Bajo el escenario de neutralidad actuarial, la investigación realizada pone de manifiesto como las reformas en la edad legal de jubilación actualmente en marcha pueden no ser suficientes para corregir las desviaciones esperadas en el número medio de años de vida tras la jubilación.
- Hacer uso de la garantía hipotecariaPublication . Ayuso, Mercedes; Bravo, Jorge; Holzmann, Robert; NOVA Information Management School (NOVA IMS); Information Management Research Center (MagIC) - NOVA Information Management SchoolEl cambio demográfico en curso, la disminución de los niveles de adecuación de los sistemas tradicionales de seguridad social de reparto, las reformas estructurales de los planes de pensiones y la reducción del apoyo familiar tradicional han aumentado la necesidad de ahorro privado adicional para cubrir la diferencia de ingresos de las personas de edad avanzada. En este documento explicamos la necesidad, la función y la viabilidad de los sistemas de movilización de capital para complementar las pensiones públicas y privadas de manera integrada. Utilizamos los últimos datos europeos de la Encuesta sobre la Situación Financiera y el Consumo de los Hogares (HFCS) del Eurosistema para analizar la composición de la riqueza de los hogares y el proceso de acumulación en la zona del euro. Para cuantificar el volumen del patrimonio familiar y su potencial para mejorar los ingresos de jubilación actuales y futuros, calculamos la relación capital-valor (ETV) para todos los países, estimamos el tiempo de pago del préstamo y calculamos la cantidad de capital inmobiliario que se espera que se libere en un período de 10 años mediante pagos hipotecarios mensuales regulares. A continuación, catalogamos y explicamos las múltiples alternativas de gestión y acceso al patrimonio familiar a lo largo del ciclo de vida, y destacamos las principales características, riesgos, ventajas e inconvenientes de los dos productos más importantes del mercado (planes de reversión de vivienda e hipotecas inversas). Por último, explicamos los principales obstáculos y retos de la demanda y de la oferta para el desarrollo de los mercados de movilización de capital y extraemos algunas implicaciones de política.
- Revisión del ahorro y el desahorro en el ciclo de vida entre las tres capas de grupos de ingresosPublication . Ayuso, Mercedes; Bravo, Jorge; Holzmann, Robert; NOVA Information Management School (NOVA IMS); Information Management Research Center (MagIC) - NOVA Information Management SchoolEl enfoque basado en el ciclo de vida es el ejemplo de modelo de decisiones de ahorro de los particulares. Supone que los individuos prefieren un flujo de consumo constante durante su ciclo de vida ahorrando hasta su jubilación y gastando sus ahorros después. La realidad no suele concordar con esta hipótesis, dando lugar a nuestro modelo hipotético de ciclo de vida de tres niveles por grupos de ingresos. El nivel de bajos ingresos ahorra poco, por lo que tiene un desahorro bajo; el nivel de ingresos altos ahorra durante su vida activa y a menudo se beneficia de herencias, pero no se produce desahorro a menos que se vea afectado por un problema grave; solo el nivel medio se comporta en general según lo previsto. Se supone que el motivo de este comportamiento diferenciado es triple: entorno externo, por ejemplo, múltiples cambios; diferencias en las preferencias, por ejemplo, tendencias de comportamiento y entornos e intervenciones institucionales, por ejemplo, provisiones de renta mínima. Este artículo describe las hipótesis respectivas, presenta soporte conceptual y empírico inicial y revisa la literatura internacional sobre las hipotéticas causas. La revisión de bibliografía internacional no echa por tierra nuestra hipótesis de una aplicación reformulada y amplia de tres niveles del modelo de ciclo de vida, pero ofrece algunas precisiones y surcos iniciales. El artículo propone los siguientes pasos conceptuales y empíricos, a saber: enriquecer las estimaciones existentes sobre distribución de la riqueza en el momento de la jubilación con estimaciones sólidas de los recursos de la seguridad social (pensiones y sanidad, realizar pruebas orientadas de verificación de hipótesis sobre los factores clave con datos del panel de hogares y formular respuestas normativas si las nuevas hipótesis no son rechazadas.
- Making use of Home EquityPublication . Holzmann, Robert; Ayuso, Mercedes; Bravo, Jorge Miguel; NOVA Information Management School (NOVA IMS); Information Management Research Center (MagIC) - NOVA Information Management SchoolThe demographic change underway, declining adequacy levels from traditional pay-as-you-go old-age social security systems, structural reforms in pension schemes and the reduction in the traditional family support have increased the need for additional private savings to cover the old age income gap. In this paper we discuss the necessity, the role and the viability of home equity release schemes in supplementing public and private pensions in an integrated way. We use the latest European data from the Eurosystem Household Finance and Consumption Survey (HFCS) to analyse the household's wealth composition and accumulation process in the euro area. To quantify the size of the housing wealth and its potential to enhance existing and future retirement income, we compute the equity-to-value ratio (ETV) for all countries, estimate the time to loan payoff and compute the amount of home equity that is expected to be released over a 10-year period through regular monthly mortgage payments. We then catalogue and discuss the many alternative options for managing and accessing housing wealth over the life cycle, and highlight the main characteristics, risks, advantages and drawbacks of the two most important market products (home reversion plans and reverse mortgages). Finally, we discuss the main demandside and supply-side obstacles and challenges to the development of equity release markets and extract some policy implications.