Search

In this paper the relative efficiency of the forest sector of 28 EU/EFTA countries during the period 2010–2015 is assessed using Data Envelopment Analysis (DEA). Three non-discretionary inputs (persons employed, forest available for wood supply and initial growing stock) are considered. The outputs are roundwood production, gross value added and final growing stock. The proposed DEA model not only computes efficiency scores but also improvement targets. The countries with the lowest efficiency scores during the period under study are Greece, Bulgaria and Italy. In the second stage, a fractional regression model is fitted and the factors that have an influence on the estimated efficiency are identified. The factors that have an influence are GDP and belonging to the NORTH Europe and CENTRAL-WEST Europe regions. Quantitative estimates of the partial effects of these factors are provided. The results can contribute in providing guidance towards the best practice in roundwood production. [ABSTRACT FROM AUTHOR]

The paper provides fresh empirical evidence on the tourism-growth relationship for Greece over the period 1977Q1-2020Q2. We find that the long-run relationship between tourism and output is positive and is characterized by a substantially faster adjustment of output after a negative shock than after a positive one. Using asymmetric error-correction model analysis the results show that the short-term adjustment path occurs through the level of output for negative deviations from the long-run equilibrium, thus supporting the tourism-led growth hypothesis. Linear quantile regression (QR) analysis indicates that the impact of tourism remains positive across the output distribution, but the effect is more pronounced at the lower quantiles of output while at the higher quantiles of output it becomes weaker and statistically insignificant. Furthermore, applying asymmetric QR analysis there is evidence that tourism growth exhibits an asymmetric impact on output growth. Our results have important policy implications, since the tourism-led growth hypothesis is a useful policy recommendation, but it should not be considered a panacea. [ABSTRACT FROM AUTHOR]

This paper aims to investigate the impact that the capital structure of a firm has on its stock price performance. We apply regression analysis at a sample consisting of Greek listed non-financial companies over the period 1998-2009, both at the full sample level and at four leverage deciles. In doing so, we test if leverage is priced as a risk factor by constructing a leverage factor. The main contribution of our work is that we diversify capital structure studies by broadening the limited work that has been accomplished on the base of leverage as an explanatory variable of returns. Our findings show that the leverage risk factor contains significant information content and that it adds a considerable portion in the explanation of stock returns. [ABSTRACT FROM AUTHOR]

The present paper describes the results of experiments with measurements of heavy metals concentrations in soil, leaves and roots of Zea mays cultivated near the major road in the area Araxos, Greece. The chain of ecological interactions is decomposed into individual subsystems with sufficiently small number of data samples describing concentrations of elements. The GMDH-based regression models are obtained and analyzed to assess different aspects of interactions within the chain “soil–roots–leaves”. The paper also represents a qualitative assessment technique to simplify analysis of the results, as well as to generalize the modeling results for different subsystems to the whole system. [ABSTRACT FROM AUTHOR]

The paper studies the earnings differential between genders in Greece employing quantile regression analysis and applying a variant of the selection-adjusted Oaxaca and Ransom () decomposition methods to explain the components of the wage differentials. The results suggest that, in Greece, substantial differences in wages between men and women can be identified. Decomposing the wage gap between genders the results show that the difference in wages is attributed mainly to the unexplained part and to a lesser extent to the employee’s endowment. In all deciles of the wage distribution the wage differentials between genders are not explained by differences in the productive characteristics of the employed but rather they constitute the unexplained part of the wage differential. [ABSTRACT FROM AUTHOR]

The paper presents the findings of a study of the decision-making process which precedes the choice of a university in Greece. Specifically, the degree of rationality exhibited by prospective students is assessed in an attempt to provide a test for the economic approach to the explanation of human behaviour. Information search is used as an indication of rationality and measured through a survey conducted among 220 university students in the academic year 2003/2004. The findings provide weak support for the rationality postulate in that they indicate that more than 40% of respondents could not be classified as information seekers. Logistic regression analysis was used in order to identify characteristics associated with the propensity to engage in information search: high socioeconomic status students, students who perceived the decision as important, and students who had acquired information prior to the choice of a university were found to be more likely to engage in information search. The paper draws attention to the limitations of the economic rational man model of human behaviour and discusses the implications of the findings for the promotional strategy of universities. [ABSTRACT FROM AUTHOR]

In this paper, 28 aftershock sequences are selected, which are distributed in different areas including north China, southwest of China, northwest of China, Taiwan area, Turkey and Greece. In order to investigate the characteristics of these sequences along with different temporal and spatial coordinates, each sequence has been divided into dozens of segments called ``sub-sequences''. The ETAS (Epidemic Type Aftershock Sequences) model is applied to each ``sub-sequence'', and therefore the vectors of parameters of ETAS could be evaluated. Another model named LR (Logistic Regression) model is used to seek the correlate relation between the parameters of ETAS applied to every earthquake ``sub-sequence'' and seismicity. All the analyses and estimations imply that the characteristic of decay of aftershock sequences in different temporal and spatial domains seems to be characterized by the parameters of the ETAS model applied to some aftershock sequences or ``sub-sequences'', and there are some proportional correlate relations between the evaluation of LR model and the occurrence probability of the succeeding strong seismic energy release. [ABSTRACT FROM AUTHOR]

The paper examines the asymmetric transmission effects of financial assets, liabilities, and housing wealth on consumption in Greece, during the period 1999Q4–2017Q4 by applying threshold autoregressive methodology developed by Enders and Siklos (J Bus Econ Stat 19(2):166–176, 2001) and Stevans (Quant Finance 4(2):191–198, 2004). The results show that (1) there is a long-run equilibrium relationship among consumption, income and net wealth components, (2) consumption responds asymmetrically to all types of changes applied, and (3) there is evidence for the predominance of negative changes compared to positive ones. The empirical findings are consistent with a stronger consumption response to decreases in financial and housing wealth and add to the existing literature in that the driving force of the rapid decrease in consumption is the deleveraging change. Lastly, the robustness analysis, by applying Hansen's (J Bus Econ Stat 35(2):228–240, 2017) kink regression model, confirms that consumption and net wealth components data fit better to threshold than to linear models. [ABSTRACT FROM AUTHOR]

Maritime networks of coastal and insular countries constitute fundamental transportation systems affecting the economy and the developmental dynamics of their countries. Under this perspective, the present article studies the Greek Maritime transportation Network (GMN), by using a complex network approach for the part of structural analysis and empirical techniques for the socioeconomic evaluation of the GMN's topology. A methodological framework is developed for dealing with the GMN's disconnectivity, which is evaluated by the empirical analysis. The curve fitting procedure on the degree distribution data indicated the existence of some scale-free network properties of the GMN, which seemed to be also captured as high correlations between pairs of binary and their homologous distance-weighted node structural variables, electing a topic of further empirical research on various networks. This status implies a kind of GMN's structural indifference to distance, favoring the development of transportation activities into greater distances within the GMN. Also, the linear regression analysis modeled the connectivity of the GMN, electing topological, spatial and socioeconomic information. Finally, this paper elected the utility of complex network analysis in the study of national maritime networks, capable in providing new insights to the transportation policy makers of Greece. [ABSTRACT FROM AUTHOR]

Copyright of Bulletin of Engineering Geology & the Environment is the property of Springer Nature and its content may not be copied or emailed to multiple sites or posted to a listserv without the copyright holder's express written permission. However, users may print, download, or email articles for individual use. This abstract may be abridged. No warranty is given about the accuracy of the copy. Users should refer to the original published version of the material for the full abstract. (Copyright applies to all Abstracts.)

Copyright of Bulletin of Engineering Geology & the Environment is the property of Springer Nature and its content may not be copied or emailed to multiple sites or posted to a listserv without the copyright holder's express written permission. However, users may print, download, or email articles for individual use. This abstract may be abridged. No warranty is given about the accuracy of the copy. Users should refer to the original published version of the material for the full abstract. (Copyright applies to all Abstracts.)

Copyright of Bulletin of Engineering Geology & the Environment is the property of Springer Nature and its content may not be copied or emailed to multiple sites or posted to a listserv without the copyright holder's express written permission. However, users may print, download, or email articles for individual use. This abstract may be abridged. No warranty is given about the accuracy of the copy. Users should refer to the original published version of the material for the full abstract. (Copyright applies to all Abstracts.)

This empirical paper uses annual data for Greece 1960–2000 to study the link between fiscal policy and economic growth. Our regression analysis implies that, although a smaller public sector can be good for growth, it is necessary to look beyond size; the composition and quality/efficiency of the public sector are equally important. The policy lesson is that a smaller government share in GDP, a reallocation of funds away from the wage bill to public investment, and an improvement in government quality/efficiency can become engines of long-term growth. [ABSTRACT FROM AUTHOR]

The design of efficient water allocation systems depends, among other factors, on economic issues and, above all, on a reliable estimate of the economic value of water. In this paper the hedonic price method is utilized to reveal the implicit value of irrigation water by analyzing agricultural land values in Chalkidiki, a typical rural area in Greece. The method was applied to a sample of both irrigated and nonirrigated properties and the value of irrigation water was estimated by disaggregating the total price of each parcel of land, obtained through a local survey. Results show that, apart from typical value attributes, the agricultural characteristics of the land, including irrigation water availability, have a significant influence on land prices. [ABSTRACT FROM AUTHOR]

The aim of this paper is to improve our understanding of the empirical determinants of firm growth by extending the literature to include a new group of variables related to foreign direct investment (FDI), namely the degree of foreign ownership and technology spillovers. Based on recent developments in the field, our analysis also encompasses the role of sunk costs and financial constraints, while quantile regression techniques are adopted as more suitable to the data available (2,640 manufacturing firms operating in Greece in the 1992–1997 period). Our findings highlight the role of FDI in increasing firm growth with varying intensity depending on industry groups and regression quantiles, and vindicate the use of new variables. [ABSTRACT FROM AUTHOR]

Research has repeatedly confirmed that farmer field schools (FFS) can serve as a bridge between science and farm practice, enhancing simultaneously rural social energy. However, even though social capital is a burgeoning topic in FFS research, it is not clear whether and how it mediates FFS performance. In this mixed-methods study, using data from two FFS projects conducted in Greece, we examined if social capital among trainees facilitates the co-creation of knowledge and the co-development of agricultural innovations by farmers. A thematic analysis was performed to analyse qualitative data, whereas regression models were employed for the quantitative strand of analysis. Results revealed that social capital evolves progressively during FFS, enabling the achievement of the project's aims by enhancing in-group communication, establishing affective ties, instilling a sense of community, and triggering motivational contagion among participants. Statistical analyses confirmed that the "softest" sides of social capital (bonding and connection) significantly contribute to knowledge and innovation co-production. Although this work was based on data derived only from two FFS projects that took place in Greece, our findings underline the importance of social capital for the success of any FFS project and emphasise the need for identifying routes to nurture social capital within FFS. [ABSTRACT FROM AUTHOR]

Purpose: Vancomycin-Resistant Enterococci (VRE) are important causes of Intensive Care Unit (ICU) infections. Our goal was to identify the prevalence and risk factors for VRE colonization upon ICU admission and during ICU stay, as well as, their impact in enterococcal infection including vancomycin-susceptible cases (VSE). Methods: A prospective study regarding patients admitted in ICU ( n = 497) was conducted during a 24-month period. Rectal swabs were collected upon admission and during hospitalization and inoculated onto selective medium. Enterococci were phenotypically characterized. van genes were investigated by PCR and clones were identified by Pulsed-Field Gel Electrophoresis and Multilocus Sequence Typing. Epidemiologic data were collected from the ICU database. Results: Risk factors for VRE carriage upon ICU admission (71/497) were: duration of previous hospitalization, glycopeptide administration, chronic heart failure, malignancy, insulin-dependent diabetes mellitus, and previous enterococcal infection (VRE and/or VSE). Risk factors for VRE colonization during ICU stay (36/250) were: quinolone administration, chronic obstructive pulmonary disease, chronic renal failure, and number of VRE-positive patients in nearby beds. Risk factors for enterococcal infection during ICU stay (15/284), including VRE and VSE cases, were: administration of third- or fourth-generation cephalosporins, cortisone use before ICU admission and VRE colonization, whereas, enteral nutrition was a protective factor. Conclusions: Previous VRE colonization and antibiotic usage are essential parameters for enterococcal infection (by VRE or VSE) during ICU stay. Previous enterococcal infection, co-morbidities and antibiotic usage are associated with VRE colonization upon ICU admission, whereas, patient to patient transmission, co-morbidities and antibiotic usage constitute risk factors for VRE colonization during ICU hospitalization. [ABSTRACT FROM AUTHOR]

Canopy fuel characteristics that influence the initiation and spread of crown fires were measured in forty representative Aleppo pine ( Pinus halepensis Mill.) stands in Greece. Aleppo pine canopy fuels are characterized by low canopy base height (CBH) (2.0-6.5 m), while available canopy fuel load (CFL) (0.63-1.82 kg/m) and canopy bulk density (CBD) (0.07-0.22 kg/m) values are similar to those of other conifers worldwide. Regression equations for the estimation of canopy fuels were developed based on common stand parameters. Stand basal area was the best-fitted predictor for the estimation of CFL and CBD at stand level, explaining 77 and 74 % of the observed variation, respectively. Regression analysis failed to provide any significant estimates for the CBH. Prediction of canopy fuel characteristics based on stand basal area can be useful in fuel management and fire prevention planning since it and can be easily incorporated into existing forest inventory systems and can be used for the Kyoto protocol requirements of carbon changes in Aleppo pine forests located in Greek sites. [ABSTRACT FROM AUTHOR]

This study examines Greek teachers' perceptions related to the nature and management of autistic children. To investigate these issues, a statistically reliable number of questionnaires ( n = 228) was distributed to a diversified teacher population. The questionnaire responses were analyzed statistically to identify the explanatory power of critical independent variables. The research findings support that teachers' specialized training and working experience are critical inputs to improve teachers' perceptions and efficient serving of autistic children. A cumulative joint effect of teachers' previous specialized education and working experience working with autistic children was also indicated. This could be supportive of teachers upgrading their active leading role in team working with specialized scientific staff, parents and institutions on autistic children. [ABSTRACT FROM AUTHOR]

Knowledge of compressional and shear wave velocities is necessary to estimate the physical, dynamic and mechanical properties of rocks with an indirect, but easy, fast and economical way. Although, many attempts have been made to correlate the wave velocities with the rock characteristics, only few studies have been concentrated on ultrabasic rocks and especially on peridotites. The aim of this study is to apply correlation analysis to investigate the relationships between wave velocities and rock properties for peridotites. Thus, 35 fresh peridotite samples (non or slightly serpentinized ultrabasic rocks), taken from the western part of Othrys mt and the Kallidromo mt (central Greece) were tested. The relationships between P and S wave velocities and the rock properties are described by simple regression analyses and the confidence intervals are presented as well. The study reveals strong positive, linear correlations between the P and S wave velocities. Positive, linear relationships are also indicated between wave velocities and unit weight and mechanical properties, while the increase of effective porosity causes decrease of the wave velocities. The wave velocities are exponentially affected with serpentinization percentage, while the best fit equations between wave velocities and primary minerals are logarithmic. The wave velocities and the micropetrographic index I are strongly correlated by both exponential and linear functions, but exponential trends present higher determination coefficients. [ABSTRACT FROM AUTHOR]

The article discusses a study on whether differences in technical efficiency derived from data envelopment analysis (DEA) and stochastic frontier analysis (SFA) can be explained by factors of the external operating environment. Topics include the study focusing on technical efficiency in dialysis facilities, the tendency for factors of the external environment to influence management's ability to transform inputs into outputs, and the potential role of DEA and SFA in informed decision-making.

Our analysis is based on the 2008 Athens Area Study and exploits detailed information regarding health impairments and labour market outcomes for Greek males. Distinguishing between healthy and heath-impaired employees who have or do not have work limitations, the unobserved productivity effect of health is separated from discrimination. We then estimate a regression model that includes terms to correct for employment selection and endogenous stratification of self-reported health condition. A penalty for productivity limitation exists. Evidence of wage discrimination is also found. Both findings are statistically significant and highlight the necessity for instituting active policies against unequal treatment. [ABSTRACT FROM AUTHOR]

Maternal smoking during pregnancy is a significant threat to the fetus. We examined the association between active maternal smoking and smoking cessation during early pregnancy with newborn somatometrics and adverse pregnancy outcomes including preterm delivery, low birth weight, and fetal growth restriction. One thousand four hundred mother-child pairs with extensive questionnaire data were followed up until delivery, within the context of a population-based mother-child cohort study (Rhea study), in Crete, Greece, 2007-2008. Comparing smokers to nonsmokers, the adjusted odds ratio (OR) was 2.8 [95% confidence interval (CI), 1.7, 4.6] for low birth weight and 2.6 (95%CI: 1.6, 4.2) for fetal growth restriction. This corresponded to a 119-g reduction in birth weight, a 0.53-cm reduction in length, and a 0.35-cm reduction in head circumference. Smoking cessation early during pregnancy modified significantly these pregnancy outcomes indicating the necessity for primary smoking prevention. [ABSTRACT FROM AUTHOR]

Abstract  The aim of this study was to prove that altitudinal variability of average monthly and annual precipitation is better summarised when the altitude observed within a radius of several kilometres around a meteorological station is taken into consideration, instead of the altitude of the station itself. The use of the variable Z′, which combines the altitude of the closest mountain with its distance from the station, is compared against the use of altitude alone in simple linear and multiple quadratic regression equations for the altitudinal interpolation of precipitation over Greece. The data-set comprised precipitation observations from 516 meteorological stations. The comparison between the two variables is discussed on the basis of the resulting determination coefficients (R2) and standard errors of estimate (S). For all seasons, except summer, it was found that the variable Z′ improves the predictive ability of the regression equations, thus showing its potential for further use in interpolation procedures. [ABSTRACT FROM AUTHOR]

The article presents a study which examines the ex-dividend day stock price and trading volume behavior in the Greek stock market between 2000 and 2004. The ex-dividend stock price anomaly was analyzed by the authors using both standard event-study methodology and cross-sectional regression analysis. The authors discovered that stock prices drop less than the dividend amount in the country's stock market.

Statistical downscaling techniques have been developed for the generation of maximum and minimum temperatures in Greece. This research focuses on the four conventional seasons, and three downscaling approaches, Multiple Linear Regression using a circulation type approach (MLRct), Canonical Correlation Analysis (CCA) and Artificial Neural Networks (ANNs), are employed and compared to assess their performance skills. Models were developed individually for each variable (Tmax, Tmin), station and season. The accuracy of downscaled values has been quantified in terms of a number of performance criteria, such as differences of the mean and standard deviation ratios between observed and modelled data, the correlation coefficients of the two sets, and also the RMSEs of the downscaled values relative to the observed. All methods revealed that during the cool season Tmax tends to be better reproduced, whereas Tmin is overestimated, particularly over western Greece, which is characterised by higher orography. With respect to the warm season, the simulation of Tmax reveals greater divergence, whereas Tmin is better generated. The distinction between the three techniques is somewhat blurred. None of the methods were found to be superior to the others and each has been shown to be a good estimator in some cases. This study concludes that all proposed methods comprise useful tools for simulating daily temperatures, as the high correlation coefficients, between observed and downscaled values, have demonstrated. However, the importance of local factors, which affect the natural variability of temperature, has been emphasised indicating that the geography of a region constitutes an important and rather complex factor, which should be included in models to improve their performance. [ABSTRACT FROM AUTHOR]

The source identification of trace elements emitted into Athens (Greece) atmospheric environment has been studied by the Enrichment Factor (EF) and by Principal Component Analysis (PCA). The prevailing wind direction is related to EF data in order to identify the possible pathways of trace elements, in the Athens basin. As gas pollutants and trace elements could be emitted from the same source, the possible relation between these two groups is studied by PCA and correlation relations. According to EF data, the trace elements Fe, Sm, Th, Co, Sc, Cr and K have a crustal origin while the elements Zn, As, Sb, Ag, Br result of anthropogenic pollution. The study of the prevailing wind direction showed that the existing geophysical channel in the northern area of Athens basin could be a pathway for the entrance of Fe, La, Sm, Th, Co, Cr, Na and Ag into Athens atmosphere. On the contrary, the sea breeze could be a potential cleaner of the atmosphere from the same elements. Six source factors were resolved by PCA for all the Athens area explaining the 90% of the total variance. They could nominated as soil dust, central heating, movement of cars, car tires, car break abrasion and sea breeze. After the application of PCA and the linear regression model, the concentration of atmospheric ozone shows to have a positive significant correlation with Na and Zn and a negative significant correlation with As, Br, Ce, Co, Cr, Fe, La, Sb, Sc, Sm. A possible explanation of the mechanism for the decrease of atmospheric ozone concentration in relation to trace metals is given according to the existing literature data. [ABSTRACT FROM AUTHOR]

Productivity and its relation to air temperature and precipitation of 11 deciduous woody fodder species was studied in a semi-arid Mediterranean environment with cold winters in Macedonia, Greece. The species studied included six shrubs: Amorpha fruticosa L., Carpinus orientalis Mill, Colutea arborescens L., Corylus avellana L., Fraxinus ornus L. and Ostrya carpinifolia Scop.; and four trees: Pirus amygdaliformis Vill., Quercus pubescens Wild., Quercus sessiliflora Salish. and Robinia pseudoacacia L., with two accessions, common and spineless. Fodder species were established as one-year-old seedlings in 1987 and studied through 1994. Productivity was measured by clearcutting of the aboveground annual biomass (DM) at the end of each growing season. Samples of biomass were hand separated to determine the grazeable material (leaves and twigs). In addition, monthly values of air temperature and precipitation were correlated with annual biomass through a multiple linear regression analysis. It was found that annual biomass was statistically different among species in all the study years with Robinia being the most productive of all the species tested followed by the other two legumes Colutea and Amorpha. Proportion of grazeable material ranged widely among species and years with an overall mean of 50%. Robinia produced grazeable biomass more than 1000 kg/ha followed by Amorpha and Colutea with about 800 and 700 kg DM/ha, respectively, while all the other species produced less than 500 kg DM/ha. Yearly variation in annual biomass was found to be affected much more by air temperature, especially during the beginning of the growing season (March), than by precipitation. Coefficients of determination (rh>) were found to be high (0.50–0.80) in Amorpha, Pirus, Quercus and Robinia but only in the latter two species they were high enough (>0.70) so that the relations produced can be used for predictive purposes. [ABSTRACT FROM AUTHOR]