This paper attempts to extend the theoretical and empirical methodology employed in previous literature, by proposing a utility maximization process to estimate the optimal tax revenue from a sample of 30 countries. It is shown that an optimal tax system is defined solely by two crucial determining factors: The productive capacity of the country (GDP) and consumers’ preferences (consumption spending). All the other variables can be disregarded, as macroeconomic determinants (GDP, consumption) tend to capture the impact of all the remaining factors on tax revenue. It is also shown that our utility maximization method generates tax-effort indices which do not differ significantly from those of IMF and World Bank studies. The actual tax burden for most of the sample countries is shown to be below its optimal level. As expected, the tax-effort performance of each of the sample countries appears to be affected by the variety of approaches employed throughout the text.

This paper examines the spillover effects transmission mechanism between oil prices, oil price uncertainty and oil price volatility on labour market in Greece, using static and dynamic quantile connectedness methodology (Diebold and Yilmaz Diebold and Yilmaz, Int J Forecast 28:57–66, 2012; Ando et al. Ando T, Greenwood-Nimmo N, Shin Y (2018) ‘Quantile connectedness: Modelling tail behavior in the topology of financial networks’, Working Paper. https://ssrn.com/abstract=3164772.). There is empirical evidence that the oil price variable is the most influential node of the energy variables on hirings and firings, suggesting the endogeneity of the labour market variables. Rolling estimation analysis based on the quantile VAR to capture the volatility spillovers across the whole conditional distribution shows a large variation of the total connectedness index, which is responsive to exogenous adverse and beneficial shocks. Further, our results point to a strong effect due to the COVID-19 pandemic and the state intervention to sustain the pandemic on the labour market. Overall, the analysis reveals a substantial higher time-varying connectedness of the system at the tails of the distribution, indicating that changes in energy markets asymmetrically affect the Greek labour market in recessionary and flourishing states of the economy, rather than normal times.

The paper draws on the economic theory of alliances to stress the importance of considering both benefits and costs arising from the 0interaction between member states of a military alliance in terms of defence expenditure on equipment. We expand the theory of alliances to incorporate the spills...

This study delves into the exploration of asymmetries in the field of Digital Economics (DE) and specifically, within the digital construction sector, unraveling intricate relationships that guide its evolutionary journey. To unveil the complex relationship between GDP growth rates and Digital Construction (DC) we leverage the Digital Economy and Society Index (DESI), employing a panel dataset encompassing 27 European Union (EU) countries over the period 2017-2022. As a foundational tool for our empirical analysis, we perform Quantile via Moments regression, thus introducing this novel methodology to digital construction research. The findings reveal a consistent and statistically significant positive impact of DC on GDP growth rates, across the entire spectrum of economic conditions, but the effect is more pronounced at the upper quantiles of output. This result implies that stronger economies can use more efficiently the benefits of the Digital Construction compared to the weaker economies, thus signaling the need of the latter for structural reforms, to improve the integration rate of digitalization in the construction sector. The pronounced influence of the Human Capital component of DC underscores the pivotal role of nurturing human skills to effectively integrate digital construction techniques into infrastructure development, within a collaborative culture.