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Climate-Smart Agriculture in West Africa: A Quantitative Assessment of Crop-Specific Resilience and Environmental Thresholds in Sierra Leone (2000–2024)
No full text2. Abstract
Background: Sub-Saharan African agriculture is increasingly threatened by the acceleration of climate-driven volatility. In Sierra Leone, where over 60% of the population relies on rain-fed subsistence farming, the lack of crop-specific climate risk data poses a critical barrier to food security planning. While national yields have grown due to post-conflict stabilization, the underlying biological thresholds of primary staples remain poorly understood, leaving the agricultural sector vulnerable to "tipping points" in thermal and hydrological stress.
Objective: This research investigates the multi-decadal impact of climate variability on agricultural productivity in Sierra Leone. By integrating satellite-derived hydrological data with national production statistics, the study aims to identify crop-specific sensitivities to environmental stressors and establish biological temperature thresholds for staple crops.
Methodology: The study utilizes a fused dataset combining FAOSTAT yield records, NASA soil moisture metrics, and localized atmospheric data from the Climate Initiative portal. A robust data science pipeline was employed, involving Z-score standardization, log-transformations for precipitation skewness, and the engineering of quadratic temperature terms. Ordinary Least Squares (OLS) regression models with interaction terms were utilized to evaluate the differential resilience of major staples, including Rice, Sorghum, Maize, and Cassava.
Results: Findings reveal that while technological and infrastructural progress (Year) remains the primary driver of yield growth (), agricultural output is increasingly constrained by non-linear temperature thresholds (). Notably, the analysis identifies Sorghum as a highly resilient staple, demonstrating a unique ability to maintain yield stability during significant rainfall volatility (), whereas Rice exhibits higher vulnerability to thermal anomalies. Furthermore, results suggest that excessive precipitation and drainage constraints currently present a higher statistical risk to productivity than drought.
Conclusion: The study provides empirical evidence for the prioritization of drought-tolerant and flood-resilient cultivars in national food security policies. These findings offer actionable insights for climate adaptation strategies in West Africa, emphasizing the need for crop diversification and improved hydrological infrastructure to buffer against accelerating environmental volatility
Governance Quality and the Creative Economy: A Multi-dimensional Analysis of Asian Countries
No full textThis study investigates the multidimensional effects of governance quality on the development of the creative economy in 31 Asian countries over the period 2002–2023. Employing fixed-effects (FE) estimations and the System Generalized Method of Moments (System GMM) to address endogeneity and dynamic panel bias, the findings reveal that all dimensions of governance quality exert positive and statistically significant effects on creative economy performance, although their magnitudes differ substantially across dimensions. Control of corruption, government effectiveness, and regulatory quality emerge as the most influential drivers, while rule of law, political stability, and voice and accountability also play important roles in expanding and sustaining creative economic activities. These results reaffirm the central importance of governance as an institutional foundation for creative economy development and highlight the complementarity - rather than substitutability - among governance pillars. By providing comprehensive quantitative evidence for Asia, this study contributes to the literature and offers policy-relevant insights for fostering innovation, strengthening commercialization capacity, and unlocking the creative potential of Asian economies
Dualisme des régimes de change et contrainte de coordination des politiques économiques en République Démocratique du Congo
No full textThis paper analyzes the effects of exchange rate regime dualism on the coordination of economic policies in the Democratic Republic of the Congo (DRC). Although the country officially adopted a floating exchange rate regime in 2001, the economy remains highly dollarized and characterized by persistent segmentation between the official and parallel foreign exchange markets. This institutional mismatch raises concerns about the effectiveness of macroeconomic policy coordination.
Using annual data for the period 1995–2024, the study applies a linear econometric model in which inflation serves as a synthetic indicator of macroeconomic coordination. The model includes the degree of dollarization, money supply growth, the fiscal deficit, and an indicator capturing foreign exchange market dualism. The results indicate that inflation dynamics in the DRC are mainly driven by monetary expansion and changes in the degree of dollarization. Exchange rate market dualism influences inflation indirectly by weakening monetary transmission mechanisms. Furthermore, the shift to a floating exchange rate regime in 2001 does not appear to have generated a significant structural break in inflation behavior.
These findings suggest that the primary constraint on macroeconomic coordination in the DRC does not stem from the formal exchange rate regime choice itself, but rather from the coexistence of a de jure floating regime and a de facto highly dollarized monetary system. The paper underscores the importance of coherent and credible policy strategies aimed at strengthening monetary credibility and improving coordination among monetary, fiscal, and exchange rate policies
Анализ конкуренции и доминирования в секторе страхования в Сербии в 2010–2024 гг.
No full textRussian. В статье исследуется конкуренция и доминирование на страховом рынке Сербии (за исключением Косово и Метохии). Был применен метод матрицы SV (Strength vs Variety), причем необходимые показатели рассчитаны на основе общей суммы страховых премий, собранных страховыми компаниями, согласно данным Национального банка Сербии за период 2010–2024 годов. Результаты показали относительно высокую общую степень концентрации (CRSV), а также относительно низкую дифференциацию внутри доминирующей группы (HTSV). Согласно результатам, сектор позиционировался в квадрантах RO (в годах 2010, 2011, 2015 и 2016) и B4 в остальных годах, с исключением 2012, когда обрелся в квадранте G. Кроме того, в последние несколько лет (начиная с 2020 г.) наблюдается явная тенденция снижения обоих ключевых показателей, определяющих матрицу SV: CRSV и HTSV, что свидетельствует о приближении к RO-квадранту рынка SV, т.е. усилении роли конкуренции как внутри доминирующей группы, так и по отношению к другим участникам рынка.
English. The article investigates competition and dominance in the insurance market in Serbia (excluding Kosovo and Metohia). The SV (Strength vs Variety) matrix method was applied, and the required indicators were calculated based on the total insurance premiums collected by insurance companies, according to data from the National Bank of Serbia for the period 2010–2024. The results showed a relatively high overall degree of concentration (CRSV), as well as relatively low differentiation within the dominant group (HTSV). According to the results, the sector was positioned in the RO quadrant (in the years 2010, 2011, 2015 and 2016) and B4 in the remaining years, with the exception of 2012, when it fell into the G quadrant. In addition, in last few years (since 2020) it is observed a clear tendency to decrease in both key indicators that define the SV matrix: CRSV and HTSV, which shows an approach to the RO quadrant of the SV market, i.e. a strengthening of the role of competition both within the dominant group and in relation to other market participants
Weighted Pro-Rata: Exploration of a Promising New Music Streaming Remuneration System
No full textDespite driving the recent resurgence of music industry revenue, digital streaming platforms (DSPs) face persistent criticism over the fairness of their pro-rata royalty payout systems, sparking legislative initiatives in the EU, US, and UK. This article asks how much of the perceived unfairness in DSPs’ pro-rata payouts can be ascribed to platforms offering disparate types of music consumption without any organizational separation, and how the status quo could be improved. DSPs offer access to large libraries of records that users can browse and play from, as well as “programmed” listening features, e.g. editorial or algorithmic playlists. The latter channel constitutes 40% of Spotify streams by now, and pays at the same rate per stream as the former channel. Since DSPs pay by streams market share, boosting the streams of some artists via algorithmic or editorial promotion diminishes the payout for all others. I develop empirical and theoretical arguments for why paying every stream the same price is suboptimal, by presenting disconnects between the pure number of streams and consumers’ level of engagement with content. This suggests that under the pro-rata model, the payment distribution does not accurately reflect consumers’ preferences. I further show how a stream-source weighted pro-rata system aka active engagement model can increase the pay rate for active streams by up to 67% depending on the choice of the weighting factor, hereby diminishing the financial impact of platforms’ promotion choices and rewarding artists for creating music that consumers want to actively seek out
When Does Digitalization Pay Off? The Role of Culture Across the Income Distribution
No full textDigitalization boosts economic performance, but its returns vary widely across countries. This paper shows that culture - measured via a World Values Survey index of effort, success, and technological openness - acts as a threshold moderator: internet usage raises log GDP per capita by 0.021 below the cultural threshold (-0.37) vs. 0.033 above it, using 55-country averages (2017-2024). Threshold regressions and quantiles reveal stronger effects in high-culture regimes and upper income quantiles, extending Haller (2024) globally with non-linearities. Results are robust across digitalization proxies (internet, fixed broadband, mobile cellular), implying infrastructure alone fails without cultural readiness for innovation
Determinantes de la eficiencia técnica relativa en proyectos de inversión financiados por el BCIE: Evidencia basada en DEA y modelo de variables censuradas
No full textThis study assesses the relative technical efficiency of investment projects financed by the Central American Bank for Economic Integration (CABEI) over the period 2010-2024, evaluating their capacity to transform financial resources into development outcomes. A two-stage approach is applied, combining Data Envelopment Analysis (DEA) with bias correction via bootstrap and a censored regression model to examine efficiency determinants. The results indicate an average technical efficiency of 35%, with substantial heterogeneity across projects, countries, and sectors. The benchmarking analysis identifies a limited set of projects defining the efficient frontier. Moreover, efficiency is associated with both microeconomic factors related to project design and implementation and macroeconomic conditions in recipient countries
After the Mine Closes: Institutional Design and the Governance of Long-Lived Environmental Liabilities
No full textAbandoned mine sites pose persistent environmental and public health risks long after production has ceased, yet remediation outcomes vary widely across jurisdictions. This paper examines why severe, well-documented hazards do not necessarily lead to institutional closure. Using asbestos mining as a stress case, the analysis compares remediation governance in Italy and Canada under conditions of extreme hazard severity and long latency between exposure and harm. Drawing on New Institutional Economics, the paper develops a comparative framework organized around five institutional variables: assignment of liability, decision authority and coordination capacity, information production and retention, time horizon alignment, and risk-bearing. The findings show that hazard severity and scientific certainty, while sufficient to generate political attention, are insufficient to produce durable remediation outcomes. Italy’s consolidation of authority within a purpose-built remediation institution enabled sustained action over multi-decade horizons, while Canada’s fragmented allocation of responsibility resulted in prolonged management, delayed closure, and reliance on compensation and litigation. The results demonstrate that abandoned mine remediation is fundamentally an institutional design problem rather than a technical one. More broadly, the paper contributes to institutional economics by extending its analytical lens to post-industrial closure, highlighting how governance structures shape the management of long-latency environmental liabilities across sectors
Salario Mínimo y Tiempo de Cuidado de los Hijos en EEUU, 2019-2023
No full textLa literatura económica reciente sugiere que los incrementos en el salario mínimo pueden dar lugar a que los padres dediquen más tiempo al cuidado de los hijos al aliviar las restricciones financieras, como el efecto renta. Sin embargo, la mayor parte de la evidencia de investigaciones pasadas no analiza las disrupciones de la pandemia de COVID-19.
Esta investigación examina el impacto de los aumentos del salario mínimo a nivel estatal en el tiempo de cuidado infantil de los padres en los Estados Unidos durante el periodo mencionado de 2019 a 2023. Mediante el uso de microdatos de la American Time Use Survey (ATUS), analizamos una muestra de 4.043 padres en edad laboral y encontramos que, a diferencia de los hallazgos del periodo 2003-2019, no existe un efecto estadísticamente significativo en el tiempo de cuidado infantil en las especificaciones agregadas o de subgrupos, incluyendo madres, padres y padres con bajo nivel educativo, entre otros. Este resultado nulo diverge de la literatura anterior a 2019. Atribuimos esta falta de significatividad a las rigideces estructurales únicas del mercado laboral post-pandemia (2019-2023) y a la erosión de los salarios reales debido a la alta inflación, lo que probablemente neutralizó los incentivos de comportamiento típicamente asociados con los suelos salariale
Climate Risk and Macroeconomic Vulnerability in Côte d'Ivoire: Estimating Transmission Channels, Extreme Tail Risks and Adaptation Returns via a Bayesian CLIMADA–DSGE–AIN-CGE Framework
No full textThis paper develops and estimates a structural Bayesian DSGE model with explicit climate
productivity shocks for Côte d'Ivoire — the CLIMADA–DSGE–AIN-CGE framework — building
on the Koffi (2021) macroeconomic backbone. The model integrates three analytically distinct
blocks: a climate productivity factor Ω_t estimated via Metropolis–Hastings MCMC from
CLIMADA–SODEXAM physical damage data; a calibrated Adaptive Input–Output Network
(AIN-CGE) extension capturing sectoral propagation; and a separate Extreme Value Theory (EVT)
analysis of damage tail behaviour using the Peaks-over-Threshold method. With a 90% nonRicardian household fraction, climate shocks transmit directly to aggregate consumption without
intertemporal smoothing, generating a cumulative climate multiplier of −1.32 at horizon Q8 —
approximately 1.6× the Koffi (2021) fiscal benchmark. The GPD shape parameter (ξ̂ = 0.278, CI₉₀:
[0.197, 0.361]) statistically rejects the Gaussian assumption (LR = 48.3, p < 0.001), implying
systematic under-provisioning of contingency reserves. Adaptation investment simulations yield
B/C ratios above 2.1× across all robustness scenarios. The model is confronted with IMF, World
Bank, and IPCC projections through qualitative directional comparison; all simulation results are
conditional on the estimated DSGE structure and maintained modelling assumptions