In this paper, we propose a modified formulation of the principal components analysis, based on the use of a multivariate Cauchy likelihood instead of the Gaussian likelihood, which has the effect of robustifying the principal components. We present an algorithm to compute these robustified principal components. We additionally derive the relevant influence function of the first component and examine its theoretical properties.
Two new distributions are proposed: the circular projected and the spherical projected Cauchy distributions. A special case of the circular projected Cauchy coincides with the wrapped Cauchy distribution, and for this, a generalization is suggested that offers better fit via the inclusion of an extra parameter. For the spherical case, by imposing two conditions on the scatter matrix we end up with an elliptically symmetric distribution.
Compositional data arise in many real-life applications and versatile methods for properly analyzing this type of data in the regression context are needed. When parametric assumptions do not hold or are difficult to verify, non-parametric regression models can provide a convenient alternative method for prediction. To this end, we consider an extension to the classical k-NN regression, termed a-k-NN regression, that yields a highly flexible non-parametric regression model for compositional data through the use of the a-transformation.
In this paper, we employ a meta-regression analysis approach to synthesize empirical evidence on the average partial effects of eleven adoption determinants that regularly appear in empirical studies examining farmer's adoption behavior worldwide. Our analysis considers a total of 122 studies from the adoption literature using discrete choice models that are published in 24 peer-reviewed journals since 1985, covering farmer's adoption behavior around the world and for a wide variety of agricultural technologies.
This paper develops a novel empirical framework for estimating individual emission levels in a nonpoint source (NPS) pollution problem. For doing so we incorporate into the GME model suggested by Kaplan et al., (2003) a specific theoretical structure describing both crop production technology and nature's residual generating mechanism based on the multiple production relations model suggested by Murty et al, (2012) fitted into a parametric stochastic framework.
The paper calculates the top income shares in Greece from 1967 (the seizure of power by the military dictatorship) until 2017 (the aftermath of the debt crisis). This long-run perspective allows for the examination of the relationship between inequality and institutional transformations, namely democracy, finance and crisis. We find in particular that (a) transition to democracy did not affect the income share of the top decile, whereas social democracy had a significant negative impact (b) financial development and liberalization substantially increased all top decile shares (c) debt crisis, consolidation and recession were beneficial for the upper ranks of the top decile.
We used data from a 6-year survey of 60 apiaries in Greece and economic modelling to assess at the field level the effects of neonicotinoid insecticides on honey production. Based on production function estimates, we found that sub-lethal concentrations of two widely used neonicotinoid insecticides (imidacloprid and thiamethoxam) detected in the nectar of flowers resulted in substantial losses in honey production for commercial beekeepers in our sample.
In this paper we investigate whether the price of gold is affected by internal and external macroeconomic performance, which is reflected in exchange rate movements
This paper develops a consistent theoretical framework for measuring irrigation water effectiveness and its impact on productivity growth rates by assuming a smooth transition process from traditional to modern irrigation technologies among individual farmers.
Using ten years of data on infringement lawsuits, the study reveals how firms that operate in distinctly different product markets attack each other in overlapping factor markets.
Focusing on the dominant role of Germany as the leading economy in the EMU, we test the progress of markets integration between Germany and selected EMU countries. For comparison reasons, we examine the same research question between Germany and selected non-EMU countries.
This article examines 10-year bond yields convergence between each of the new EU countries and Germany, including a structural break that embodies the effects of the current debt crisis in the Eurozone. The analysis is based on a new definition of bond yields convergence that can be interpreted either as strong or weak monetary policy convergence, depending on whether the conditions of UIP and ex-ante PPP hold or are violated, respectively.
Using an international sample of commercial banks, we find that diversification in terms of income, earning assets, and on and off-balance sheet activities influences positively their financial strength
Using a panel of firms listed in the North American and U.K. stock markets, we find that adding board directors from countries with different levels of genetic diversity (either higher or lower) increases firm performance
The results show that the size of the MFIs has a robust non-linear, inverted U-shaped impact on overall performance. Age and the status of non-governmental institution also appear to matter. As it concerns the country-level attributes, GDP growth has a robust positive impact on overall performance. Regional differences also appear to matter
Based on an endogenous growth model, we extent Roubini and Sala-i-Martin (1993) theoretical framework to analyse empirically the relationship between economic growth, announced tax rate and tax monitoring expenses using data from 32 OECD countries during the 1999-2007 period.
We assess the impact of the Eurozone’s economic policies on specific South-Eastern European countries. Since these countries are connected to the EU or the Eurozone and the economic interdependence among them is evolving, we carried out our analysis using the VECMX framework.
In the present paper we assess the impact of the Eurozone’s economic policies on specific South-Eastern European countries, namely Bulgaria, Croatia, Cyprus, Greece, Romania, Slovenia and Turkey.
In this paper, we investigate the monetary transmission mechanism through interest rate and real effective exchange rate channels.
In this article we investigate the role of information transmission in promoting agricultural technology adoption and diffusion. We study the influence of two information channels, namely extension services and social learning.
The present paper studies the relative efficiency between hotels operating under a brand and hotels operating independently, in the island of Crete, Greece, using the Data Envelopment Analysis.
The present study aims to empirically analyze the competing effects of social interactions and conversion subsidies on the adoption of organic farming practices.
The present paper extents the existing literature providing a theoretically consistent framework for decomposing TFP growth taking into account the indirect effect of pesticides use on farm production.
We employ a linear unit root test as well as a nonlinear two-regime Threshold Autoregressive (TAR) unit root test to determine whether inflation differentials in the Eurozone during the period 1970-2009 were persistent or transitory.
We allow for monetary, real, and financial variables to assess the relevant importance of each of the variables to exchange rate volatility in the case of selected EMU members and candidate countries.
This paper investigates whether the nominal euro exchange rate against the currencies of China, Japan, the UK and the USA converges or not to its equilibrium level.
We use data from the 2008-09 Athens Area Study (AAS) to provide the first evidence on the relationship between sexual orientation and earnings in Greece. The AAS asks male adults a direct question about their sexual orientation: about 4.52% self-identify as homosexuals and 0.86% as bisexuals.
In this paper, we investigate the implications of measurement errors in the daily published stock prices on the creation and management of efficient portfolios.
This paper investigates the existence of any linear or non-linear diachronic relationship between the financial newspapers circulations and the General Index of the Athens Stocks Exchange (ASE).
A variety of standard forecasting accuracy criteria and one suggestion are applied to evaluate the OECD's macroeconomic forecasts for Greece for the aggregate demand and output, the GDP implicit price deflator, the investment, the imports and the exports of goods and services.
This paper examines the strategy of investing in selected East European stock markets: The Czech Republic, Hungary, and Poland.
The aim of this exploratory research is to offer information for the set-up of a new eco-business. The Romanian eco-businesses understood the necessity of development and implementation of the latest patterns in order to assure a sustainable development of the business. The entrepreneurs are conscious about the poor state of it in comparison with other European companies.
In the current study having considered the fundamental points the first ever correspondence testing was conducted in order to test whether job applicants living with HIV (still) face prejudices in the crucial stage of the selection process in Greece.
The present study examines the relation between real stock returns and real industrial production (IP) growth for the UK and the US.
We investigate for the individual and relative accuracy of two major market power tests: the Herfindahl Hirschman Index (HHI), and the merger simulation model of unilateral effects. We propose a methodology to compare the predictive and screening power of both tests by implementing them in a hypothetical economy.
This article develops a dynamic game-theoretic model of optimizing strategic behaviour by football teams.
This study is the first to apply econometric tools in the study of wage discrimination for the integrated Romani population.
In the present study, we conducted the first ever Correspondence Test in order to test whether job applicants who voluntarily disclose their HIV infections face prejudices in the selection process in Greece.
This study provides evidence on the relationship between lesbian women and their hiring prospects by employing the Correspondence Test for Greece.
The current research contributes to two areas that have attracted scarce research attention in Greece: the experimental investigation of housing discrimination and discrimination by ethnicity. The results of this study have implications for understanding some of the enduring patterns of ethnic discrimination in the housing market.
The purpose of the paper is twofold. Firstly, we test the validity of the PPP hypothesis for selected CEEC (Czech Republic; Hungary; Poland and Slovak Republic). Secondly, we attempt to define those countries' trade linkages between Euro Area; US and the rest of the world.
The current research contributes to the small academic literature on the economics of discrimination according to sexual orientation in Europe.
In this paper drawing from the theoretical framework developed by Shieh et al., (2002), we present an endogenous growth model to empirical analyze the growth maximizing allocation of public capital among military spending and investment in infrastructure.
Due to the assumption that the best practice methods refer to each input separately instead of the whole set of inputs used by a firm, the benchmark technology as defined in the stochastic varying coefficient frontier model may be infeasible and theoretically improper whenever the maximum response coefficients are not coming from the same production unit. To overcome this problem we suggest an alternative procedure for measuring output-oriented and input-specific technical efficiency inspired from the maximum likelihood formulation of the non-neutral frontier model.
This paper examines the validity of the purchasing power parity between each of the twelve new EU countries vis-à-vis the Eurozone.
In this study, we attempt to examine the possibility of emergence of significant fluctuations of the exchange rates in the future for the candidate EMU countries.
The paper investigates whether low skilled male Albanians face unequal treatment in the Greek labour market, two years after the national adoption of the European anti-discrimination employment legislation.
This paper sheds light on the importance of the validity of PPP hypothesis for the accessing process of the candidate countries towards EMU.
In this paper we test the effects of temporal aggregation (disaggregation) on the efficiency of portfolio construction using the mean variance optimization approach
This paper proposes an alternative way of testing FOREX efficiency for developing countries
The Inverse Almost Ideal Demand System is employed for the empirical analysis of the demand for organic, integrated-agriculture, and conventional fresh vegetables, using a cross section data surveyed in Rethymno, Greece during the 2005-06 period.
The present paper develops an econometric model for measuring input-oriented technical efficiency when the underlying technology is characterized by the lack of substitution between inputs.
The present paper incorporates the Cornwell, Sickless and Schmidt (1990) flexible specification of the temporal pattern of technical efficiency into technical inefficiency effects model. The proposed formulation is then applied to the agricultural sector of the EU and US, during the period 1973-1993.
Using a stochastic frontier approach and a tranlog input distance function, this paper implements the input-oriented Malmquist productivity index to a sample of Greek aquaculture farms.
This paper suggests an alternative way for estimating the gravity equation that takes into consideration country-pair heterogeneity in bilateral trade flows.
The objective of this paper is to present a theoretical framework that conceptualizes technology adoption as a decision process involving information acquisition by farmers who face yield uncertainty and vary in their risk preferences.
This paper extends the primal decomposition of TFP changes to the case of non- neutral production frontiers. Output growth is decomposed into input growth (size effect), changes in technical efficiency, technical change, and the effect of returns to scale.
The main objective of this paper is to enrich our knowledge on the true effect of real money balances on the production process.
Utilizing a stochastic frontier approach, this paper examines the importance that input-oriented technical and scale efficiency may have for Greek cotton farmers in the context of the current EU cotton policy.
The objective of the paper is to model the degree of organic farming adoption as well as the importance of technical information acquisition in the adoption decision process.
The generalized quadratic Box-Cox transformation is used to test the relative performance of alternative, widely used, functional forms and to examine the effect of prior choice on final efficiency estimates.
This paper provides an empirical comparison of time-varying technical inefficiency measures obtained from the econometric estimation of different specifications of the stochastic production frontier model.
This paper provides a decomposition of output growth among olive-growing farms in Greece during the period 1987-1993 by integrating Bauer’s (1990) and Bravo-Ureta and Rieger’s (1991) approaches.
A stochastic Cobb-Douglas production frontier is used to provide estimates of output-oriented technical efficiency, input-oriented technical efficiency, input allocative efficiency and cost efficiency for a sample of seabass and seabream farms in Greece.
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