Search Results (4,617)

Geopolitical instability can reshape trade routes, prices, and energy-security risks. Using a monthly country-level panel from January 2015 to June 2025, this study estimates a difference-in-differences (DID) model for the logarithm of China’s fossil-fuel import values (USD) from Russia and four Central Asian suppliers relative to seven comparison suppliers. The corrected benchmark coefficient is −0.582. This estimate means that after March 2022, import values from the treated suppliers were lower relative to the counterfactual trend represented by the control group; it does not mean that every treated supplier experienced an absolute decline. Indeed, several country- and commodity-specific import values increased in levels, partly because the outcome combines quantity and price effects. Commodity-specific international price benchmarks are included as controls, but physical-volume data are not available in the submitted dataset. With only 11 country clusters, conventional clustered significance levels are interpreted cautiously. A 500-assignment placebo exercise provides a randomization-based robustness check, with no simulated coefficient as extreme as the benchmark estimate (empirical p ≤ 0.002 under the stated assignment scheme). Logistics performance, government stability, and energy OFDI are positively associated with import values in conditional regressions; because the article does not report interaction terms, these results are not interpreted as moderation effects. The findings support targeted attention to corridor reliability and supplier diversification, while broader operational policies require additional evidence. Full article

This study investigates whether the determinants of dividend policy differ across distinct dimensions of distribution. Whereas most empirical studies rely on a single measure, generally the payout ratio, we adopt a multidimensional approach that distinguishes the decision to pay a dividend, payout intensity, and dividend yield. The analysis is based on a balanced panel of 33 firms listed on the Casablanca Stock Exchange over 2003–2025, yielding 759 firm-year observations. Each dimension is estimated using an econometric strategy tailored to its statistical properties: a random-effects logit model with firm-clustered robust standard errors for the payment decision, a random-effects model with firm-clustered robust standard errors for the payout ratio, and a fixed-effects model with Driscoll–Kraay standard errors for dividend yield, following a sequential model-selection and diagnostic procedure. The findings reveal substantial heterogeneity across the three dimensions of dividend policy. Profitability primarily affects the decision to pay and dividend yield, while firm size emerges as the most pervasive determinant. Financial leverage significantly reduces both the probability of paying a dividend and the payout ratio. The most distinctive result concerns the Price-to-Book ratio: its effect is positive for the payment decision and payout ratio, but negative for dividend yield. A battery of robustness checks confirms the stability of the main findings. Overall, the results show that the determinants of dividend policy depend on the dimension examined and underscore the value of a multidimensional framework for understanding payout decisions in emerging markets. Full article

Data centers are large and rapidly growing electricity consumers, and cooling systems account for a substantial share of their energy demand. A key contribution of this study is a climate-sensitive, hourly techno-economic comparison of three data-center cooling configurations under consistent operating assumptions: a conventional water-cooled centrifugal chiller baseline, a magnetic bearing chiller (MBC) system, and an MBC system integrated with aquifer thermal energy storage (ATES). The comparison is performed for Phoenix, Arizona, and Fairbanks, Alaska, which represent substantially different cooling climates in the U.S. Hourly simulations use identical information technology (IT) load profiles, identical aggregate installed chiller capacity represented by two 4058 kW chiller units, common water-side economizer controls, and site-specific weather and electricity tariffs. Results show that the MBC system reduces annual cooling-system electricity consumption from 1169.4 to 957.4 MWh in Phoenix (18.1%) and from 361.6 to 319.4 MWh in Fairbanks (11.7%). Peak cooling-system electrical demand decreases by 119.4 kW in Phoenix and 71.6 kW in Fairbanks. Relative to the centrifugal baseline, the MBC case gives a 5.8-year simple payback in Phoenix but is not economically attractive in Fairbanks under the assumed tariff. The MBC-only case gives the lowest annual cooling electricity use in both climates. The MBC+ATES case is treated only as a screening-level, discharge-assisted cold-storage scenario rather than a full techno-economic assessment of seasonal ATES, and no site-specific hydrogeological feasibility assessment is performed. Under the assumed O&M cost structure, MBC+ATES gives a higher discounted value of savings than MBC-only, but this economic result is not caused by additional cooling-electricity savings relative to MBC-only. The MBC+ATES case also has a longer payback period because of its higher capital cost. These results show that the value of advanced cooling configurations depends on climate, free-cooling availability, electricity pricing, storage assumptions, and economic assumptions within the modeling framework considered in this study. Full article

This study was conducted to examine the perceptions and attitudes of final-year veterinary students regarding the Official Minimum Fee Schedule established for veterinarians in Türkiye, within a multidimensional framework. The research was conducted with a total of 216 final-year students enrolled in veterinary faculties in Türkiye. Data were collected using a questionnaire consisting of Likert-type items. The construct validity of the scale was assessed using Exploratory Factor Analysis (EFA), and its reliability was measured using Cronbach’s alpha coefficients. The study found that the majority of students considered providing services below the official minimum fee schedule to be ethically inappropriate and reported that professional organizations play an important regulatory and supervisory role in this regard. In terms of demographic variables, no statistically significant differences were found in factor scores based on gender, income level, university, level of education, or internship experience. However, significant differences were identified in the dimensions of regulatory–deontological attitudes and price transparency based on place of residence. In conclusion, attitudes toward the minimum fee schedule in veterinary medicine are shaped not only by legal knowledge but also by ethical values, professional socialization processes, and institutional norms. These findings highlight the importance of addressing fee policies in veterinary education together with their ethical and professional dimensions, as well as strengthening the awareness-raising role of professional organizations. Full article

A fixed-odds contract on short-horizon price direction has a positive expected value only when its win probability exceeds the break-even rate implied by the payout ratio. A deployable predictor must also produce signals at a sufficiently stable rate. We formulate this setting as selective prediction with a coverage constraint and combine a five-seed gradient-boosting ensemble over a 90-dimensional causal feature panel with daily adaptive quantile thresholds, each estimated from the preceding 14 to 28 days of model scores, with parameters selected on training data alone. Configurations are frozen after three chronological pseudo-out-of-sample folds and evaluated on a held-out period from 1 January to 10 June 2026, and the whole procedure is then repeated on a quarterly re-freezing cadence over seven successive windows. Across BTC and ETH at 5- and 10-min horizons, with a payout of 0.8 and a 55.56% break-even rate, the models execute 10.4 to 11.0 trades per day, and all four selective win rates exceed break-even. Under a dependence-aware block bootstrap, three of four remain significant, and within a 32-test confirmatory family, two survive Holm–Bonferroni correction. Coverage stays inside the operational band in 26 of 28 re-frozen windows. Compared under one execution protocol, a fixed calibration slice drifts out of band while a trailing window does not, and adaptive conformal inference (ACI) matches the proposed rule on coverage when its step size is tuned but not otherwise, whereas an outcome-driven conformal controller reduces coverage by more than an order of magnitude. The expected value is insensitive to exchange fees, which consume under 5% of the measured edge, and sensitive to the payout term. Under matched feature sets, training pools, and coverage, most of the apparent cross-asset difference does not persist. This paper presents a proof of concept for the framework rather than making any claim about cryptocurrency predictability. Full article

The massive integration of variable renewable energy sources (vRES) in Central Europe is fundamentally transforming electricity price formation and straining transmission grids. However, existing academic metrics, such as the RES Capture Price, offer only a static view of investor revenues and fail to capture dynamic market rigidity and systemic risks during periods of high instantaneous vRES penetration. This study addresses this literature gap by introducing two novel and transparent methodological parameters: Market Exposure to Green Overproduction (MEGO) and the Price Divergence Coefficient (PDC). Formulated as conditional non-parametric indicators, the MEGO index quantifies the conditional probability of price collapse and the loss of market elasticity during hours when vRES penetration exceeds critical thresholds (α = 0.50 to 0.80) of systemic load. Conversely, the PDC index measures the frequency of substantial price non-convergence across neighbouring bidding zones (CZ, PL, FR) relative to the German reference market (DE). Based on an extensive dataset spanning from 2015 to mid-2026—capturing the transition to 15 min market time units— the empirical results reveal a distinct change in market behaviour. While the frequency of price collapse during high-vRES periods was lower in earlier years and temporarily reduced during the 2022 energy crisis, the post-crisis period (2024–2026) exhibits substantially higher MEGO values, with periods in which wind and solar generation exceeded 80% of instantaneous system load being associated with prices at or below 0 EUR/MWh in up to 60% of the evaluated intervals. Concurrently, the PDC analysis reveals persistent spatial price non-convergence, particularly in France and Poland. These patterns coincided with major changes in European electricity-market conditions, including the implementation of Core Flow-Based Market Coupling, variations in nuclear availability and evolving cross-border network conditions; however, the PDC indicator alone does not permit causal attribution to any individual factor. The proposed MEGO and PDC parameters provide policymakers, transmission system operators (TSOs), and investors with an intuitive diagnostic framework for dimensioning grid flexibility, energy storage, and cross-border infrastructure in the decarbonization era. Full article

This paper studies how hidden, stochastic continuation of informed participation shapes price discovery in a two-period Kyle-type market. Hidden participation separates two analytical questions that coincide in the standard Gaussian-linear model. Conditional on a specified linear continuation order, we first derive the exact Bayesian posterior mean and variance of a mixture comprising an informed-trading regime and a noise-only regime; this is a conditional-inference result, not a full nonlinear equilibrium. We then derive an equilibrium under a constrained best-linear-pricing protocol in which market makers use the minimum-mean-square-error affine projection and the insider optimizes pointwise against linear prices. The exact Bayesian posterior responds nonlinearly because order flow reveals both residual value and the likelihood of informed participation, while moderate flows can preserve substantial regime uncertainty. In the projection benchmark, a lower continuation probability accelerates first-period information revelation, shifts insider rents toward the initial round, and creates opposing early- and late-learning effects. A dimensionless analysis characterizes how inference varies with continuation probability and the informed-to-noise variance ratio and establishes scale invariance for the benchmark’s normalized comparative statics. The paper thus isolates a participation margin in price discovery and states precisely which results concern exact inference and which concern a constrained equilibrium. Full article

Underground gas storage (UGS) facilities serve to balance natural gas networks within a given area. The nature of natural gas network balancing is twofold: long-term (seasonal) during periods of significant gas withdrawal (the cold half-year) and short-term (daily) during periods of peak natural gas demand throughout the day. The first type of balancing has been a standard characteristic for many years, covering increased demand during the winter season. In contrast, the importance of daily balancing is growing alongside the ongoing energy transition, where natural gas-based power generation sources flexibly replace renewable energy sources that are dependent on the time of day or weather conditions. The necessity for increased balancing of energy systems makes them more sensitive to crisis situations. This article presents the key role of UGS as a fundamental resilience factor for European energy systems, particularly in the face of energy crises triggered by geopolitical instability. Conflicts are redefining the role of UGS as a pillar of energy security. This study analyzes how strategic gas reserves mitigate the effects of sudden supply disruptions and price shocks caused by geopolitical factors. It describes impact scenarios of two conflicts: Russia’s invasion on Ukraine and the conflict in the Persian Gulf leading to the closure of the Strait of Hormuz. While UGS is essential for the short-term management of natural gas supply flows, its long-term value lies in providing a “strategic buffer” that allows energy systems to adapt to unforeseen geopolitical conflicts. Integrated storage management is indispensable for maintaining the operational integrity of the European transmission and energy system during periods of heightened instability. The paper also identifies necessary directions for the development of UGS systems. Between 2016 and Q1 2026, the share of eastern gas imports declined from over 40% to 5.2%, while LNG increased to 41.7% of total inflows, confirming the strategic importance of underground gas storage in maintaining energy system resilience. Full article

Vietnam’s domestic gold price has persistently exceeded the world price by a wide margin, even as recent reforms have begun to relax the state’s historical monopoly over gold-bar production and imports. This paper asks why the gap persists, and whether it is confined to normal market conditions or extends into periods of extreme price movement. Using daily data spanning 2 January 2019 to 31 July 2026 (1856 trading days), covering the reform introduced by Decree No. 232/2025/ND-CP we decompose the domestic premium into a currency component and a pure physical-gold component, and use a copula-based framework to separately assess average price linkage and tail (extreme-event) co-movement between the domestic and world markets. Domestic gold bars traded at an average premium of 16.0% over import-parity world prices, of which 13.8 percentage points reflect the physical-gold component driven by constrained arbitrage, while currency factors account for only about 2 percentage points. The average linkage between the two markets is weak, indicating persistent segmentation, and this segmentation extends into the tails of the distribution for most of the sample. The premium itself carries substantial latent risk: a reversion to price parity would imply a one-off loss of about 9.6% of value, roughly eight to ten times the historical one-day 5% Value-at-Risk. Following the reform’s effective date, however, we find early evidence of emerging co-movement specifically in extreme upside price movements, even though the physical premium itself has not yet narrowed—consistent with a reform that has been enacted in law but remains at an early stage of operational implementation. The results indicate that administrative restrictions on the physical gold supply chain, rather than currency controls, are the principal source of Vietnam’s persistent gold-price gap, with direct implications for how the ongoing liberalization process should be sequenced. Full article

While climate change is a significant pressure point for pollinators and honeybees, its long-term relationship with managed honeybee colonies and honey production remains unclear and context sensitive. This study, using FAOSTAT data from 1961 to 2024, examined the relationships between land surface temperature anomalies and the number of registered beehives, the constant-price honey production value, and the normalized honey production value per colony, both globally and specifically for 18 Mediterranean countries. To differentiate between long-term structural trends and short-term temperature relationships, correlation, regression, bootstrap confidence interval, temperature series sensitivity analysis, cross-correlation function, and normalized index analyses were used together. The study results show strong long-term co-movement between temperature anomalies and recorded beekeeping indicators at the global and Mediterranean scale in the level series; however, first-differenced (year-to-year) analyses show this association weakens substantially and, for Mediterranean honey production value, reverses sign, indicating that the level-series correlations are driven largely by common long-term trends. The relationship between temperature anomalies and beekeeping indicators shows a context-dependent structure among Mediterranean countries. The findings show that the increase in colony size does not always coincide with the increase in the constant-price honey production value per colony; in some cases, these two indicators can move in different directions. This indicates the need for an analytical decomposition of the dynamics of quantitative growth and economic production value per colony in the beekeeping sector. Full article

This study examines consumer preferences for goat cheese by jointly analysing sensory evaluations and willingness to pay more (WTPM) for artisanal and industrial products. Using a comparative experimental design conducted in Sicily (Italy) with 105 regular cheese consumers recruited through convenience sampling in a controlled laboratory setting, the study investigates how differences in farming systems and processing methods—from extensive pasture-based systems to intensive industrial production—affect sensory perception and WTPM. Two ordered logit models with increasing price levels were estimated to identify the determinants of WTPM, one for industrial goat cheese and one for artisanal goat cheese, including sensory evaluations and socio-demographic variables as explanatory factors. A paired t-test was also performed to assess whether sensory evaluations differed significantly between the two cheeses. The results indicate that sensory quality was the main driver of WTPM for artisanal goat cheese, with aroma emerging as the strongest sensory predictor in the exploratory ordered logit model (β = 3.535; p < 0.01). However, the sensory comparison revealed only modest differences between the two cheeses, with taste showing the clearest differentiation in favour of artisanal cheese. Among extrinsic attributes, only PDO certification positively affected WTPM, whereas the negative association observed for biodegradable packaging should be interpreted cautiously as an exploratory finding requiring further investigation. Origin-based signals such as PDO therefore appeared to enhance value alongside, rather than replace, sensory differentiation, acting as complementary rather than substitutive cues. Overall, the findings contribute to the literature on food systems and consumer behaviour by linking sensory perception with production systems and showing how artisanal dairy products can generate consumer value through the combination of sensory characteristics and extrinsic attributes related to origin and production identity. Full article

This study evaluates the economic feasibility of standalone Battery Energy Storage Systems (BESS) for energy arbitrage in the Portuguese day-ahead electricity market. A Mixed-Integer Linear Programming (MILP) model is developed to optimize the operation of BESS configurations with varying durations (2, 4, 6, and 8 h), using historical price data from 2020 to 2024. The model incorporates realistic operational constraints, and the resulting arbitrage revenues are analyzed under multiple cost scenarios. Additionally, the study performs a Net Present Value (NPV) analysis using average and year-specific price profiles and three different scenarios to assess long-term investment viability. Consistent with current market access conditions in Portugal, the analysis focuses exclusively on day-ahead market arbitrage, and alternative revenue streams (intraday, real-time, ancillary services) are discussed qualitatively due to limited liquidity and restricted participation rules. The results reveal that although BESS can generate positive cash flows in recent high-volatility years, all configurations yield negative NPVs under current cost structures and market conditions. Even with optimistic cost reductions, breakeven is not achieved, indicating that standalone arbitrage remains financially not viable. These findings highlight the importance of cost optimization and the need for complementary revenue streams or policy support to make such investments feasible in Portugal. Full article

Railway idle land offers a large and underused space for solar power, yet its economic value has not been evaluated. Revenue depends on the volatile System Marginal Price (SMP) and Renewable Energy Certificate (REC) markets, whose uncertainty cannot be fully captured by static discounted cash flow (DCF) analysis. This study asks whether solar development on Korea’s railway idle land is worthwhile over the long term, and at what scale it should proceed. It applies an integrated DCF and real options analysis (ROA) framework to a proposed 438 MW project on the Honam Line in southern Korea. Price volatility is estimated from monthly SMP and REC data with a geometric Brownian motion model, and the options to expand and to contract are valued on a binomial lattice. The DCF yields a marginal net present value of USD 3.2 million. The expansion option adds USD 172.5 million and is exercised in 67% of states, raising the total project value to USD 175.7 million. Rising panel efficiency and falling capital costs move the project firmly into feasibility. Therefore, scale flexibility turns a marginal project into a strongly positive one, supporting the large-scale deployment of solar on railway idle land. Full article

This paper analyzes the viability of Indian equity markets in response to global energy supply shocks. This study attempts to correct the missing-variable bias in earlier literature by using the USD-to-INR exchange rate as an exogenous explanatory variable. This will help determine the intricate synthetic relationship between Brent Crude Oil Returns and the carbon-efficient S&P BSE GREENEX. Vector Autoregressive with exogenous variables (VARX) models are employed to analyze the effects of structural shocks to Brent Crude Oil prices on the S&P BSE GREENEX. The empirical results found that global oil price shocks might immediately affect green equity values in India. Even without foreign currency changes, the Indian Green Exchange Index (GREENEX) maintains its long-term values, showing structural resilience. Institutional investors and Indian financial authorities, such as SEBI and the Reserve Bank of India, gain better risk-management insights amid international energy crises from this information. It also shows that carbon-efficient standards can hedge inflation induced by foreign import supply chain interruptions. Full article

This study examines both the linear and nonlinear relationship between overall Environmental, Social, and Governance (ESG) performance and firm market value, while also comparing the effects of the Environmental, Social, and Governance dimensions in publicly listed companies from the European Union. The analysis is based on an unbalanced panel of 1706 non-financial listed firms covering the period 2011–2025. Firm value is primarily measured by Tobin’s Q, with the Price-to-Book ratio and Return on Assets (ROA) used for robustness analysis. The results indicate a significant U-shaped relationship between overall ESG performance and firm value, suggesting that the value-enhancing effects of ESG emerge only after firms achieve sufficiently high sustainability performance. In contrast, the individual Environmental, Social, and Governance dimensions in most cases do not exhibit significantly different effects on firm market value. Additional subsample analyses reveal that the nonlinear relationship is more pronounced among Western European firms and companies with lower greenhouse gas emissions intensity. The findings suggest that investors primarily evaluate firms based on their overall sustainability profile rather than individual ESG dimensions. The study contributes to the ESG literature by providing further evidence of the nonlinear nature of the ESG–firm value relationship and by comparing the explanatory power of aggregated and disaggregated ESG measures within the European Union’s harmonized sustainability reporting environment. Full article