Decomposing Partial Factor Productivity in the Presence of Input-Specific Technical Inefficiency: A Self-Dual Stochastic Production Frontier Approac

The present paper provides a theoretical framework for the decomposition of partial factor productivity in the presence of input-specific technical inefficiency. Based on Kuroda’s dual approach and using the theoretical foundations developed by Kopp, we decompose the growth rate of partial factor productivity into five sources, namely, changes in input-specific technical efficiency, substitution effect, technical change, the effect of scale economies and a homotheticity and input biased technological effect. The empirical model is based on a generalized self-dual Cobb-Douglas stochastic production frontier and on the methodological approach for measuring orthogonal input-specific technical efficiency suggested by Reinhard, Lovell and Thijssen. The model is applied to a panel data set of 723 cereal farms in Greece observed during the 1994-2003 cropping period obtained from FADN. The empirical results suggest that the labor productivity of cereal farms has been increased by 2.89 per cent annually. Technical change was found to be the main source of labor productivity (70.4%), while changes in technical efficiency also contributed significantly over the period analyzed (34.7%). On the other hand, substitution effect was found to affect negatively the rate of labor productivity (-14.2%).labor efficiency and productivity growth, multilateral production frontier

Decomposition of Labor Productivity Growth: A Multilateral Production Frontier Approach

This paper develops a parametric decomposition framework of labor productivity growth relaxing the assumption of labor-specific efficiency. The decomposition analysis is applied to a sample of 52 developed and developing countries from 1965-90. A generalized Cobb-Douglas functional specification is used taking into account differences in technological structures across group of countries to approximate aggregate production technology using Jorgenson and Nishimizu (1978) bilateral model of production. Measurement of labor efficiency is based on Kopp�s (1981) orthogonal non-radial index of factor-specific efficiency modified in a parametric frontier framework. The empirical results indicate that the weighted average annual rate of labor productivity growth was 1.43 per cent over the period analyzed. Technical change was found to be the driving force of labor productivity, while improvements in labor efficiency and human capital account approximately for the 22 per cent of that productivity growth.labor efficiency and productivity growth, multilateral production frontier

mRECIST criteria and contrast-enhanced US for the assessment of the response of hepatocellular carcinoma to transarterial chemoembolization

PURPOSEWe aimed to evaluate the combination of the modified Response Evaluation Criteria In Solid Tumors (mRECIST) and contrast-enhanced ultrasonography (CEUS) as a tool for the assessment of hepatocellular carcinoma treated with transarterial chemoembolization. MATERIALS AND METHODSForty-seven hepatocellular carcinoma patients (80 target tumors suitable for mRECIST measurements) were studied. They were treated with scheduled transarterial chemoembolization with doxorubicin-eluting microspheres every 5–7 weeks. Imaging follow-up (performed one month after each transarterial chemoembolization) included a standard, contrast-enhanced modality (computed tomography [CT] in 12 patients or magnetic resonance imaging [MRI] in 35 patients) and CEUS. The study focused on response evaluation after the third transarterial chemoembolization. CEUS required a bolus injection of an echo-enhancer and imaging with a dedicated, low mechanical index technique. The longest diameters of the enhancing target tumors were measured on the CEUS or CT/MRI, and mRECIST criteria were applied. Radiologic responses were correlated with overall survival and time to progression. RESULTSThe measurements of longest diameters of the enhancing target tumors were easily performed in all patients. According to mRECIST-CEUS and mRECIST-CT/MRI, complete response was recorded in five and six patients, partial response in 22 and 21 patients, stable disease in 16 and 14 patients, and progressive disease in four and six patients, respectively. There was a high degree of concordance between CEUS and CT/MRI (kappa coefficient=0.84, P < 0.001). Responders (complete+partial response) according to mRECIST-CEUS had a significantly longer mean overall survival and time to progression compared to nonresponders (37.1 vs. 11.0 months, P < 0.001 and 24.6 vs. 10.9 months, P = 0.007, respectively). CONCLUSIONThe mRECIST-CEUS combination is feasible and has prognostic value in the assessment of hepatocellular carcinoma following transarterial chemoembolization

Human capital contributions to explain productivity differences

This paper develops a parametric decomposition framework of labor productivity growth relaxing the assumption of labor-specific efficiency. The decomposition analysis is applied to a sample of 121 developed and developing countries during the 1970-2007 period drawn from the recently updated Penn World Tables and Barro and Lee (A new data set of educational attainment in the world 1950-2010. NBER Working Paper No. 15902, 2010) educational databases. A generalized Cobb-Douglas functional specification is used taking into account differences in technological structures across groups of countries to approximate aggregate production technology using Jorgenson and Nishimizu (Econ J 88:707-726, 1978) bilateral model of production. The measurement of labor efficiency is based on Kopp's (Quart J Econ 96:477-503, 1981) orthogonal non-radial index of factor-specific efficiency modified in a parametric frontier framework. The empirical results indicate that the weighted average annual rate of labor productivity growth was 1.239 % over the period analyzed. Technical change was found to be the driving force of labor productivity, while improvements in human capital and factor intensities account for the 19.5 and 12.4 % of that productivity growth, respectively. Finally, labor efficiency improvements contributed by 9.8 % to measured labor productivity growth

Microeconomic analysis of the impacts of pesticides ise on the supply of agricultural products: the case of greenhouse farms in Ierapetra of Crete

The present dissertation aims at developing a consistent theoretical and empirical framework for the measurement of the effects of pesticides use on farmer’s productivity and analyzing the general relation between human capital and productivity. The dissertation is consisted by three parts. The first part aims at developing a complete theoretical and empirical model in order to analyze the direct effects of education on worldwide labor productivity in the presence of labor technical inefficiency and to identify quantitatively the various sources that compose it. The aim of the second part is to provide an integrated decomposition framework for the theoretical and empirical assessment of the qualitatively and quantitatively effects of two elements of human capital, namely, education and health on farm productivity. Finally, the third part of the dissertation aims at analyzing the effects of pesticides use on farmers’ health and on their productivity performance through the development of an appropriate theoretical and empirical model. All three theoretical models developed in this dissertation are based on decomposition methods of partial and total factor productivity growth, while for the empirical applications of the models we use the generalized Cobb- Douglas and Translog production functions. The results that came up from the empirical application of the three theoretical models emerge the important role played by human capital in the production process in both national level and in agricultural sector. Improvements in human capital were identified in all models to explain a significant part of productivity growth, confirming the suspicion that its absence from the analysis is possible to lead in biased and sometimes controversial results. The results from the third model indicated that greenhouse farm productivity increased 1.2826 per cent over the period analyzed. The main source of productivity growth was found to be technical change contributing (53.24 per cent) to TFP changes. Changes in labor quality due to human capital improvements were found to account for about 38.5 per cent of TFP growth, indicating the important role of human capital in Greenhouse production. Furthermore, the pesticides effect on TFP growth was 5.49 per cent, driven mainly by the biased technical change of pesticides. Finally, the health effect of pesticides on productivity was found to be weak but positive (0.86 per cent) due to the existence of decreasing returns to scale.Η παρούσα διδακτορική διατριβή έχει ως στόχο την ανάπτυξη ενός συνεπούς θεωρητικού πλαισίου για την μέτρηση των αποτελεσμάτων της χρήσης χημικών εισροών στην παραγωγικότητα των γεωργών και την γενικότερη ανάλυση της σχέσης μεταξύ ανθρώπινου κεφαλαίου και παραγωγικότητας. Η διατριβή αποτελείτε από τρία μέρη. Ο στόχος του πρώτου μέρους είναι η ανάπτυξη ενός ολοκληρωμένου θεωρητικού και εμπειρικού μοντέλου για την ανάλυση των άμεσων αποτελεσμάτων της εκπαίδευσης και της τεχνικής αποτελεσματικότητας στην παγκόσμια παραγωγικότητα της εργασίας και η ποσοτικοποίηση των διάφορων παραγόντων που την συνθέτουν. Το δεύτερο μέρος της διατριβής έχει ως στόχο την παροχή ενός θεωρητικά συνεπούς πλαισίου αποσύνθεσης (decomposition framework) με σκοπό την εμπειρική αξιολόγηση των ποιοτικών και ποσοτικών αποτελεσμάτων της εκπαίδευσης και της υγείας των γεωργών στην συνολική παραγωγικότητα τους (TFP-Total Factor Productivity). Τέλος, το τρίτο μέρος της διατριβής έχει ως στόχο την ανάλυση των αποτελεσμάτων της χρήσης εντομοκτόνων στην υγεία των γεωργών και στην παραγωγικότητα τους μέσω της ανάπτυξης ενός κατάλληλου θεωρητικού και εμπειρικού υποδείγματος. Και τα τρία υποδείγματα που αναπτύσσονται στην παρούσα διατριβή βασίζονται σε μεθόδους αποσύνθεσης της μερικής και συνολικής παραγωγικότητας και στην χρήση της γενικευμένης Cobb-Douglas και Translog συνάρτηση παραγωγής. Τα εμπειρικά αποτελέσματα που προέκυψαν από τα τρία υποδείγματα της παρούσας διδακτορικής διατριβής αναδεικνύουν τον πολύ σημαντικό ρόλο του ανθρώπινου κεφαλαίου στην παραγωγική διαδικασία τόσο σε εθνικό επίπεδο όσο και στον αγροτικό τομέα. Οι μεταβολές στο ανθρώπινο κεφάλαιο βρέθηκαν να εξηγούν ένα πολύ σημαντικό μέρος των μεταβολών της παραγωγικότητας, γεγονός που ενισχύει την άποψη ότι η απουσία του ανθρώπινου κεφαλαίου από την ανάλυση οδηγεί σε μεροληπτικά και λανθασμένα αποτελέσματα. Τα αποτελέσματα από την εμπειρική εξειδίκευση του τρίτου υποδείγματος έδειξαν ότι η συνολική παραγωγικότητα των θερμοκηπιακών καλλιεργητών στην Ιεράπετρα Κρήτης αυξήθηκε ετησίως κατά 1.2826% από το 2003-07. Η κύρια πηγή της αύξησης αυτής ήταν βελτιώσεις στην τεχνολογία (53,24%), ενώ οι μεταβολές στην ποιότητα του ανθρώπινου κεφαλαίου βρέθηκαν να εξηγούν το 38.5% της συνολικής παραγωγικότητας. Επιπλέον, η χρήση εντομοκτόνων βρέθηκε να επηρεάζει θετικά 5.49% την παραγωγικότητα. Η χρήση εντομοκτόνων βρέθηκε να επηρεάζει αρνητικά την υγεία των γεωργών στο δείγμα αλλά το αποτέλεσμα της υγείας από την χρήση χημικών εισροών βρέθηκε να είναι θετικό αλλά αδύναμο στην παραγωγικότητα (0.86%) εξαιτίας της ύπαρξης φθινουσών αποδόσεων κλίμακας

Human capital contributions to explain productivity differences

This paper develops a parametric decomposition framework of labor productivity growth relaxing the assumption of labor-specific efficiency. The decomposition analysis is applied to a sample of 121 developed and developing countries during the 1970-2007 period drawn from the recently updated Penn World Tables and Barro and Lee (A new data set of educational attainment in the world 1950-2010. NBER Working Paper No. 15902, 2010) educational databases. A generalized Cobb-Douglas functional specification is used taking into account differences in technological structures across groups of countries to approximate aggregate production technology using Jorgenson and Nishimizu (Econ J 88:707-726, 1978) bilateral model of production. The measurement of labor efficiency is based on Kopp's (Quart J Econ 96:477-503, 1981) orthogonal non-radial index of factor-specific efficiency modified in a parametric frontier framework. The empirical results indicate that the weighted average annual rate of labor productivity growth was 1.239 % over the period analyzed. Technical change was found to be the driving force of labor productivity, while improvements in human capital and factor intensities account for the 19.5 and 12.4 % of that productivity growth, respectively. Finally, labor efficiency improvements contributed by 9.8 % to measured labor productivity growth

A parametric decomposition of hotel-sector productivity growth

In this paper, we decompose hotel-sector total factor productivity growth into components attributable to changes in technical efficiency, scale effect, and technical change. The hotel-sector production Frontier is approximated parametrically using a primal approach requiring no data on output and input prices while permitting the conduction of statistical tests for the various features of the hotel-sector technology. Our empirical model relies on a flexible translog production function which allows to distinguish between Hicks-neutral and factor-biased technological progress. Using this framework, we estimate hotel-sector productivity growth and its components in a sample of 25 European countries from 2008 to 2015. Based on the empirical results, a cross-country comparison is performed and the sources of hotel-sector productivity are discussed. Finally, the implications of the study for hotel operators and policy makers are presented and a set of recommendations is developed for improving hotel sector productivity growth

Tax evasion, tax monitoring expenses and economic growth: an empirical analysis in OECD countries

Using a standard endogenous growth model with public capital accumulation enriched with tax evasion (Roubini and Sala-i-Martin in J Monet Econ 35:275–301, 1995) developed by Kafkalas et al. (Eur Econ Rev 70:438–453, 2014), we provide empirical evidence on the relationship between aggregate output growth, announced tax rate and tax monitoring expenses for a set of 32 OECD countries during the 2000–2007 period. Our results indicate that high announced tax rates above the elasticity of public capital and excess expenses on tax auditing as means of reducing tax evasion are not effective deepening the recession

Measuring the publishing productivity of economics departments in Europe

In this paper, we assess the relative performance of economics departments in Europe using publication data in a core set of thirty-five top research journals in economics during the period 2007-2011. We measure performance on the basis of a publishing productivity index which allows to account for differences in research inputs among departments. The measurement of publishing productivity index is based on counts of quality-adjusted articles per faculty using journal-weights computed over the same period with our study. Based on publishing productivity performance, comprehensive rankings are constructed at both department and country level

Informational cascades and technology adoption: Evidence from Greek and German organic growers

The present study aims to empirically analyze the effect of social interactions and conversion subsidies on the adoption rates of organic farming practices in two samples of olive and cereal growers in Greece and Germany, respectively. To this end we construct two alternative indicators to capture informational cascades created in rural areas. The first indicator is based on demographic characteristics while the other one on profitability considerations since farmers are likely to imitate the behavior of more successful farmers. Building upon the theoretical findings of Foster and Rosenweig (1995), Munshi (2004), Bandiera and Rasul (2006) and Weber (2012), we find that informational cascades are indeed important in revising farmers' perceptions and adoption behavior in both rural areas of Europe. Our results show that conversion subsidies can enhance social network effects internalizing informational externalities even in areas where adoption rates are considerable. This finding is independent of the crop and the country under consideration underlying the importance of informational cascades for technology adoption