Volatility model estimations of palm oil price returns via long-memory, asymmetric and heavy-tailed GARCH parameterization

This study attempts to model the volatility of palm oil price returns via a number of Generalized Autoregressive Conditional Heteroskedasticity class of models that capture the long-range memory, asymmetry, and heavy-tailedness phenomena. These models have been estimated in the presence of four alternative conditional distributions: Gaussian, Student t, generalized error distribution, and skewed Student t. The empirical results indicate that complex model specifications and distribution assumptions do not seem to outperform the simpler ones in terms of standard model selection criteria and numerical convergence. With regard to the conditional distributions, a symmetric fat-tailed distribution has been found to be preferred to Gaussian and asymmetric distribution in many cases

Exchange-rate risk and exports: evidence from a set of transition economies

This article investigates the hypothesis that exchange-rate risk may have an effect on exports for a set of transition countries, namely, Belarus, Kazakhstan, Russia, and Ukraine. To assess this effect, although a two-step estimation approach has earned an extensive empirical record in the literature, a number of studies in this context do not appear to support this approach due to a potential generated regressor issue. This dissonance in a two-step estimation procedure seems to have been somewhat resolved by a relatively new branch of empirical approach that exploits a multivariate version of generalized autoregressive conditional heteroskedasticity in-mean models. The findings suggest that the effect of exchange-rate risk seems to be detrimental in Belarus and Ukraine. However, for Russia and Kazakhstan, which are heavily dependent on crude oil exports, the effect has been found to be indeterminate

Supply and Demand Model for the Malaysian Cocoa Market

This paper investigates a system of supply, demand, and price equations for Malaysian cocoa using annual data over the period 1975-2008. Theoretically, in supply and demand models, the price variable is treated as endogenous. However, Hausman specification test result indicates that there is no simultaneity problem in the model. Thus, we estimate the system of equations utilizing the Seemingly Unrelated Regression (SUR) estimation technique which might be considered a more efficient estimator for supply and demand model of the Malaysian cocoa. The results suggest that the Malaysian cocoa production is mainly affected by the previous year production, price of cocoa beans at lag two as well as the harvested area. In the export demand equation, the real effective exchange rates is statistically significant determinant while the index of industrial production of advanced economies and the world price of cocoa are found to be insignificant. The results also suggest that both Malaysian industrial production index and domestic price of cocoa beans are key determinants of domestic demand for cocoa beans in Malaysia. Finally, the domestic price of cocoa beans is highly sensitive to its domestic consumption, lagged domestic price, and its world price.Supply and Demand; Malaysian Cocoa; SUR technique

Malaysian Cocoa Market Modeling: A Combination of Econometric and System Dynamics Approach

The Malaysian cocoa sector has undergone dramatic changes during the last few decades. In the early years of 1970s, this sector has maintained an upward trend in the area and consequently the production. However, the trend reversed in the late 1980s due to factors such as declining world prices, higher labour costs, widespread of cocoa pod diseases and the pull of more lucrative crops (in particular palm oil). By 2008 only about 19,976 hectares were planted with cocoa compared to a peak of 414,236 ha in 1989. Production of cocoa beans has trended down accordingly. The study combines the econometric and system dynamics approach in modeling the Malaysian cocoa market. A first order system was developed to capture the interdependencies of the major structural elements of the markets such as production, local and export demands, inventory and imports. Nevertheless, the model provides an understanding of the interrelationships between the system components and allows the simulation of policy variables changes. Future work will involve a detail examination of the interaction cocoa supply chain system (from farm to export) to provide a much more comprehensive representations of the dynamics of the market.Econometric methods; system dynamics; Malaysian cocoa market

Does fossil oil price matter? Market performance of banks in the dual banking system and policy implications

This study examines the impact of oil price shocks on the stock performance of 73 listed banks—41 conventional and 32 Islamic—across dual banking systems in net oil-exporting and importing countries. Employing panel fixed-effects and two-stage least squares (2SLS) IV regressions, we address both endogeneity and unobserved heterogeneity. The results indicate that oil price fluctuations have a significant impact on bank stock returns, with a stronger negative effect during oil price declines, particularly those driven by demand-side shocks. Islamic banks are more sensitive to these fluctuations than their conventional counterparts, reflecting greater exposure to oil-dependent macroeconomic environments. Robustness checks confirm the presence of non-linear and asymmetric effects: bank stock returns respond more adversely to falling oil prices than to increases in oil prices. These responses differ systematically across bank types and levels of national oil dependency. Our findings underscore the importance of accounting for oil price risk in bank valuation and performance forecasting. For financial managers and investors, the results underscore the importance of incorporating oil-related risk factors into portfolio management, stress testing, and pricing models. For regulators and policymakers, the evidence supports the adoption of macroprudential tools such as countercyclical capital buffers and sector-specific supervisory frameworks to strengthen banking system resilience, particularly for Islamic banks operating in oil-dependent economies. Additionally, disclosure standards should be enhanced to improve transparency around oil price exposure, enabling better-informed decision-making across all stakeholder-dependent economies

Supply and Demand Model for the Malaysian Cocoa Market

This paper investigates a system of supply, demand, and price equations for Malaysian cocoa using annual data over the period 1975-2008. Theoretically, in supply and demand models, the price variable is treated as endogenous. However, Hausman specification test result indicates that there is no simultaneity problem in the model. Thus, we estimate the system of equations utilizing the Seemingly Unrelated Regression (SUR) estimation technique which might be considered a more efficient estimator for supply and demand model of the Malaysian cocoa. The results suggest that the Malaysian cocoa production is mainly affected by the previous year production, price of cocoa beans at lag two as well as the harvested area. In the export demand equation, the real effective exchange rates is statistically significant determinant while the index of industrial production of advanced economies and the world price of cocoa are found to be insignificant. The results also suggest that both Malaysian industrial production index and domestic price of cocoa beans are key determinants of domestic demand for cocoa beans in Malaysia. Finally, the domestic price of cocoa beans is highly sensitive to its domestic consumption, lagged domestic price, and its world price

IMPROVEMENT OF PHYSICAL EDUCATION OF CHILDREN IN EDUCATIONAL INSTITUTIONS

Physical education activities are developed in accordance with the nature of instruction: to teach children basic subjects of the same class, as well as the fact that they have already mastered new physical activity; the second exercise periodically checks the level of training, academic performance and the amount of educational materials for children: the third exercise is repeated using parameters that improve children\u27s familiarity with the exercises

TERRITORIAL AND GEOGRAPHICAL LOCATION OF THE CITIES OF THE TERMIZ OASIS IN THE EARLY MIDDLE AGES

This article through written sources and archeological research analyzes changes in urban planning traditions in the Termez oasis with the spread of Islam in region, how these changes led to the conversion of large castles and villages into cities in the early Middle Ages, to the abandonment of dual system in the structure of cities, that is, the construction of new arches while preserving the arches and shahristans, and the geographical location of large and small cities in the Termez oasis, such as Chaganiyon, Sarmingon, Charmingon, Hashimgird, Navandak, Vashgird, Barangi, Budrach, Darzangi