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Distinguishing between potential sources of growth convergence for the Portuguese economy within the EU. A panel data - time series study of the aggregate production function

Simões, Marta Cristina Nunes; Duarte, Maria Adelaide Silva
Fonte: Universidade de Évora Publicador: Universidade de Évora
Tipo: Trabalho em Andamento
ENG
Relevância na Pesquisa
45.74%
What are the potential sources of growth and how is the convergence process of the Portuguese economy within the EU characterised? We answer this question by determining the most suitable specification of the aggregate production function, CES or Cobb-Douglas, for the EU countries as in Duffy&Papageorgiou (2000). If the aggregate production technology is best described by a CES production function then the potential sources of growth are wider than the ones associated with a Cobb-Douglas technology. For instance, with an elasticity of substitution between inputs greater than one (ó>1) it is possible to have endogenous growth (see Jones&Manuelli (1990), Rebelo (1991)) while for ó<1 multiple equilibriums arise (see Azariadis (1993, 1996, 2001). To test for the most suitable production function specification we consider a sample of seventeen European countries between 1960 and 1987. The tests are conducted within a panel data and time series framework based on data retrieved from the STARS database of the World Bank. Three different kinds of samples were considered: a) all the seventeen countries; b) three of the cohesion countries, Portugal, Greece, Ireland, and Iceland; and c) each country separately, and two types of production functions – one with raw labour and one with human capital adjusted labour. By considering groups of countries and not only each country separately it is possible to distinguish between each country’s behaviour and that of the average economy and also to characterise ó according to the income level of the different countries in our sample. Previous to the estimation of the non-linear production function by maximum likelihood and GMM techniques we tested the series for stationarity both in a time series and a panel data framework. We also used linear estimation techniques...

A Mixed-Integer convex formulation for production optimization of gas-lifted oil fields with routing and pressure constraints

Aguiar,M. A. S.; Camponogara,E.; Silva,T. L.
Fonte: Brazilian Society of Chemical Engineering Publicador: Brazilian Society of Chemical Engineering
Tipo: Artigo de Revista Científica Formato: text/html
Publicado em 01/06/2014 EN
Relevância na Pesquisa
45.77%
Production optimization of gas-lifted oil fields under facility, routing, and pressure constraints has attracted the attention of researchers and practitioners for its scientific challenges and economic impact. The available methods fall into one of two categories: nonlinear or piecewise-linear approaches. The nonlinear methods optimize simulation models directly or use surrogates obtained by curve fitting. The piecewise-linear methods represent the nonlinear functions using a convex combination of sample points, thereby generating a Mixed-Integer Linear Programming (MILP) problem. The nonlinear methods rely on compact models, but can get stuck in local minima, whereas the piecewise-linear methods can reach globally optimal solutions, but their models tend to get very large. This work combines these methods, whereby piecewise-linear models are used to approximate production functions, which are then composed with convex-quadratic models that approximate pressure drops. The end result is a Mixed-Integer Convex Programming (MICP) problem which is more compact than the MILP model and for which globally optimal solutions can be reached.

INFANT HEALTH PRODUCTION FUNCTIONS: WHAT A DIFFERENCE THE DATA MAKE

Reichman, Nancy E.; Corman, Hope; Noonan, Kelly; Dave, Dhaval
Fonte: PubMed Publicador: PubMed
Tipo: Artigo de Revista Científica
Publicado em /07/2009 EN
Relevância na Pesquisa
45.79%
We examine the extent to which infant health production functions are sensitive to model specification and measurement error. We focus on the importance of typically unobserved but theoretically important variables (typically unobserved variables, TUVs), other non-standard covariates (NSCs), input reporting, and characterization of infant health. The TUVs represent wantedness, taste for risky behavior, and maternal health endowment. The NSCs include father characteristics. We estimate the effects of prenatal drug use, prenatal cigarette smoking, and First trimester prenatal care on birth weight, low birth weight, and a measure of abnormal infant health conditions. We compare estimates using self-reported inputs versus input measures that combine information from medical records and self-reports. We find that TUVs and NSCs are significantly associated with both inputs and outcomes, but that excluding them from infant health production functions does not appreciably affect the input estimates. However, using self-reported inputs leads to overestimated effects of inputs, particularly prenatal care, on outcomes, and using a direct measure of infant health does not always yield input estimates similar to those when using birth weight outcomes. The findings have implications for research...

Empirical Econometric Evaluation of Alternative Methods of Dealing with Missing Values in Investment Climate Surveys

Escribano, Alvaro; Pena, Jorge; Guasch, J. Luis
Fonte: Banco Mundial Publicador: Banco Mundial
Relevância na Pesquisa
45.74%
Investment climate Surveys are valuable instruments that improve our understanding of the economic, social, political, and institutional factors determining economic growth, particularly in emerging and transition economies. However, at the same time, they have to overcome some difficult issues related to the quality of the information provided; measurement errors, outlier observations, and missing data that are frequently found in these datasets. This paper discusses the applicability of recent procedures to deal with missing observations in investment climate surveys. In particular, it presents a simple replacement mechanism -- for application in models with a large number of explanatory variables -- which in turn is a proxy of two methods: multiple imputations and an export-import algorithm. The performance of this method in the context of total factor productivity estimation in extended production functions is evaluated using investment climate surveys from four countries: India, South Africa, Tanzania...

Structural Change and Cross-Country Growth Empirics

Eberhardt, Markus; Teal, Francis
Fonte: World Bank, Washington, DC Publicador: World Bank, Washington, DC
Relevância na Pesquisa
45.86%
One of the most striking features of economic growth is the process of structural change whereby the share of agriculture in GDP decreases as countries develop. The cross-country growth literature typically estimates an aggregate homogeneous production function or convergence regression model that abstracts from this process of structural change. This paper investigates the extent to which assumptions about aggregation and homogeneity matter for inferences regarding the nature of technology differences across countries. Using a unique World Bank dataset, it estimates production functions for agriculture and manufacturing in a panel of 40 developing and developed countries for the period from 1963 to 1992. It empirically models dimensions of heterogeneity across countries, allowing for different choices of technology within both sectors. The paper argues that heterogeneity is important within sectors across countries implying that an analysis of aggregate data will not produce useful measures of the nature of the technology or productivity. It shows that many of the puzzling elements in aggregate cross-country empirics can be explained by inappropriate aggregation across heterogeneous sectors.

A Model of Gendered Production in Colonial Africa and Implications for Development in the Post-Colonial Period

Fofack, Hippolyte
Fonte: World Bank, Washington, DC Publicador: World Bank, Washington, DC
EN_US
Relevância na Pesquisa
45.74%
This paper proposes a model to analyze the implications of colonial policies for gender inequality in Sub-Saharan Africa. The model emphasizes segmentation of production under complete specialization. It shows that the colonial production model, underpinned by occupational job segregation in the agricultural sector and gender bias in the non-agricultural sector, exacerbated gender inequality by limiting employment opportunities for women outside the realm of home production and subsistence agriculture. Over the past few decades, the resilience of parameters underlying these models of colonial production has heightened the risks of macroeconomic volatility in the region, especially where the structural transformation from low to high-value-added activities has remained elusive.

The Environment as a Factor of Production

Considine, Timothy J.; Larson, Donald F.
Fonte: World Bank, Washington, D.C. Publicador: World Bank, Washington, D.C.
EN_US
Relevância na Pesquisa
45.82%
The authors develop a model of environmental resource use in production with an empirical analysis of how electric power companies consume and bank sulfur dioxide pollution permits. The model considers emissions, fuels, and labor as variable inputs with quasi-fixed inputs of permits and capital. Incorporating information from permit markets allows the authors to distinguish between user costs and asset shadow values. Their findings indicate that firms are holding stocks of pollution permits for reasons other than short-term cost savings. The results also reveal substantial substitution possibilities between emissions, permits stocks, and other factors of production. The authors speculate that anticipated secondary markets for carbon-offset inventories related to the flexibility mechanisms of the Kyoto Protocol will have similar effects for greenhouse-gas emitting firms.

Institutional Quality Mediates the Effect of Human Capital on Economic Performance

Adams-Kane, Jonathon; Lim, Jamus Jerome
Fonte: World Bank, Washington, DC Publicador: World Bank, Washington, DC
Relevância na Pesquisa
45.74%
This paper considers the relationship between institutional quality, educational outcomes, and economic performance. More specifically, it seeks to establish the linkages by which government effectiveness affects per capita income, via its mediating effect on human capital formation. The empirical approach adopts a two-stage strategy that estimates national-level educational production functions that include government effectiveness as a covariate, and then uses these estimates as instruments for human capital in cross-country regressions of per capita income. The results identify a significant and positive effect of human capital on per capita income levels, and partially resolves the inconsistency between macro- and micro-level studies of the effect of human capital on income. The results also remain robust to alternative specifications, extension to a panel setting, subsamples of the data, and fully endogenous institutions.

Implications of the Organization of the Commodity Production and Processing Industry : The Soybean Chain in Argentina

Regunaga, Marcelo
Fonte: World Bank, Washington, DC Publicador: World Bank, Washington, DC
EN_US
Relevância na Pesquisa
45.75%
The study includes four sections: i) brief production background; ii) description of the Argentine soybean value chain; iii) evolution of the main policies and institutional regimes in Argentina; iv) lessons learned related to the political economy and the industrial organization. The study describes the main policies implemented in Argentina during the last two decades which had impact on the structure of the soybean value chain and its performance. The dramatic changes registered in some of such policies, as well as in the international scenario, provide interesting background to better understand the evolution and performance of the Argentine industry in the global soybean value chain.

The Misallocation of Land and Other Factors of Production in India

Duranton, Gilles; Ghani, Ejaz; Goswami, Arti Grover; Kerr, William
Fonte: World Bank Group, Washington, DC Publicador: World Bank Group, Washington, DC
Tipo: Trabalho em Andamento
EN_US
Relevância na Pesquisa
45.72%
This paper quantifies the misallocation of manufacturing output and factors of production between establishments across Indian districts during 1989-2010. It first distills a number of stylized facts about misallocation in India, and demonstrates the validity of misallocation metrics by connecting them to regulatory changes in India that affected real property. With this background, the study next quantifies the implications and determinants of factor and output misallocation. Although more-productive establishments in India tend to produce more output, factors of production are grossly misallocated. A better allocation of output and factors of production is associated with greater output per worker. Misallocation of land plays a particularly important role in these challenges.

R&D and productivity : estimating production functions when productivity is endogenous

Doraszelski, Ulrich; Jaumandreu, Jordi
Fonte: Universidade Carlos III de Madrid Publicador: Universidade Carlos III de Madrid
Tipo: info:eu-repo/semantics/workingPaper; info:eu-repo/semantics/workingPaper Formato: application/pdf
Publicado em /12/2007 ENG; ENG
Relevância na Pesquisa
45.79%
We develop a simple estimator for production functions in the presence of endogenous productivity change that allows us to retrieve productivity and its relationship with R&D at the firm level. By endogenizing the productivity process we build on the recent literature on structural estimation of production functions. Our dynamic investment model can be viewed as a generalization of the knowledge capital model (Griliches 1979) that has remained a cornerstone of the productivity literature for more than 25 years. We relax the assumptions on the R&D process and examine the impact of the investment in knowledge on the productivity of firms. We illustrate our approach on an unbalanced panel of more than 1800 Spanish manufacturing firms in nine industries during the 1990s. Our findings indicate that the link between R&D and productivity is subject to a high degree of uncertainty, nonlinearity, and heterogeneity across firms. By accounting for uncertainty and nonlinearity, we extend the knowledge capital model. Moreover, capturing heterogeneity gives us the ability to assess the role of R&D in determining the differences in productivity across firms and the evolution of firmlevel productivity over time.

Toward a universal theory of the human group: sociological systems framework applied to the comparative analysis of groups and organizations

Burns, Tom R.; Machado, Nora; Corte, Ugo
Fonte: CIES-IUL Publicador: CIES-IUL
Tipo: Trabalho em Andamento
Publicado em //2014 ENG
Relevância na Pesquisa
45.96%
Drawing on a sociological multi-level, dynamic systems approach – actor-system-dynamics (ASD) -- which has been developed and applied in institutional, organizational, and societal analyses, we formulate a general model for the comparative analysis of social groups and organizations. This social systems approach has not been previously applied in the group area. We claim that the approach can be systematically and fruitfully applied to small as well as large groups and organizations as a methodology to understand and analyze their structure, functioning and dynamics. A group is considered a system with three universal subsystems on which any human social organization, including small groups, depends and which motivate, shape and regulate group activities and productions. The subsystems are bases or group requisites – necessary for group “functioning” and performance in more or less orderly or coherent ways; on this basis a group may be able to realize its purposes or goals(as well as possibly some members’ personal goals) and maintain and reproduce the group. The group bases consist of: first, a rule regime (collective culture)defining group identity and purpose, shaping and regulating roles and role relationships...

Is Environmentally-Friendly Agriculture Less Profitable for Farmers? Evidence on Integrated Pest Management in Bangladesh

Dasgupta, Susmita; Meisner, Craig; Wheeler, David
Fonte: World Bank, Washington, D.C. Publicador: World Bank, Washington, D.C.
Tipo: Publications & Research :: Policy Research Working Paper; Publications & Research
ENGLISH; EN_US
Relevância na Pesquisa
45.81%
Concerns about the sustainability of conventional agriculture have prompted widespread introduction of integrated pest management (IPM), an ecologically-based approach to control of harmful insects and weeds. IPM is intended to reduce ecological and health damage from chemical pesticides by using natural parasites and predators to control pest populations. Since chemical pesticides are expensive for poor farmers, IPM offers the prospect of lower production costs and higher profitability. However, adoption of IPM may reduce profitability if it also lowers overall productivity, or induces more intensive use of other production factors. On the other hand, IPM may actually promote more productive farming by encouraging more skillful use of available resources. Data scarcity has hindered a full accounting of IPM's impact on profitability, health, and local ecosystems. Using new survey data, the authors attempt such an accounting for rice farmers in Bangladesh. They compare outcomes for farming with IPM and conventional techniques...

Functional Forms and Educational Production Functions

MONTMARQUETTE, Claude; MAHSEREDJIAN, Sophie
Fonte: Université de Montréal Publicador: Université de Montréal
Tipo: Artigo de Revista Científica Formato: 411759 bytes; application/pdf
Relevância na Pesquisa
55.74%
Different Functional Forms Are Proposed and Applied in the Context of Educational Production Functions. Three Different Specifications - the Linerar, Logit and Inverse Power Transformation (Ipt) - Are Used to Explain First Grade Students' Results to a Mathematics Achievement Test. with Ipt Identified As the Best Functional Form to Explain the Data, the Assumption of Differential Impact of Explanatory Variables on Achievement Following the Status of the Student As a Low Or High Achiever Is Retained. Policy Implications of Such Result in Terms of School Interventions Are Discussed in the Paper.

Geometry of quasi-sum production functions with constant elasticity of substitution property

Chen, Bang-Yen
Fonte: Universidade Cornell Publicador: Universidade Cornell
Tipo: Artigo de Revista Científica
Publicado em 15/07/2013
Relevância na Pesquisa
45.91%
A production function $f$ is called quasi-sum if there are strict monotone functions $F, h_1,...,h_n$ with $F'>0$ such that $$f(x)= F(h_1 (x_1)+...+h_n (x_n)).$$ The justification for studying quasi-sum production functions is that these functions appear as solutions of the general bisymmetry equation and they are related to the problem of consistent aggregation. In this article, first we present the classification of quasi-sum production functions satisfying the constant elasticity of substitution property. Then we prove that if a quasi-sum production function satisfies the constant elasticity of substitution property, then its graph has vanishing Gauss-Kronecker curvature (or its graph is a flat space) if and only if the production function is either a linearly homogeneous generalized ACMS function or a linearly homogeneous generalized Cobb-Douglas function.; Comment: 10 pages. Appeared in J. Adv. Math. Stud. 5 (2012), no. 2, 90-97

Geometric classifications of homogeneous production functions

Chen, Bang-Yen; Vilcu, Gabriel Eduard
Fonte: Universidade Cornell Publicador: Universidade Cornell
Tipo: Artigo de Revista Científica
Publicado em 14/09/2013
Relevância na Pesquisa
45.84%
In this paper, we completely classify homogeneous production functions with an arbitrary number of inputs whose production hypersurfaces are flat. As an immediate consequence, we obtain a complete classification of homogeneous production functions with two inputs whose production surfaces are developable.; Comment: 11 pages; To appear in Applied Mathematics and Computation

Kaldor?s ?technical progress function? and Verdoorn?s law revisited

McCombie, John S. L.; Spreafico, Marta R. M.
Fonte: Oxford University Press Publicador: Oxford University Press
Tipo: Article; accepted version
EN
Relevância na Pesquisa
45.84%
This is the accepted manuscript of a paper published in the Cambridge Journal of Economics (McCombie JSL, Spreafico MRM, Cambridge Journal of Economics, 2015, doi:10.1093/cje/bev030). The final version is available at http://dx.doi.org/10.1093/cje/bev030; Kaldor put forward his technical progress function as an alternative to the neoclassical aggregate production function. It is shown that Verdoorn?s law is its empirical counterpart, although allowing for increasing returns to scale. However, both may be derived from an aggregate Cobb-Douglas production function. But aggregation problems and the Cambridge capital theory controversies have shown theoretically that aggregate production functions in all probability do not exist. Moreover, the only reason that estimations of ?aggregate production functions? give good results is the existence of an accounting identity. This article reconsiders the technical progress function and Verdoorn?s law, especially in the light of these problems. Nevertheless, it is shown that estimates of the law do, in fact, provide insights into the growth process very similar to those of Kaldor, but viewed from another perspective.

Teorias econômicas de oferta de educação: evolução histórica, estado atual e perspectivas; Economic theories of the supply of education: historical evolution, current state, and perspectives

Waltenberg, Fábio D.
Fonte: Universidade de São Paulo. Faculdade de Educação Publicador: Universidade de São Paulo. Faculdade de Educação
Tipo: info:eu-repo/semantics/article; info:eu-repo/semantics/publishedVersion; ; ; ; ; ; Formato: application/pdf
Publicado em 01/04/2006 POR
Relevância na Pesquisa
45.88%
Este artigo preocupa-se com uma faceta particular (o lado da oferta) de uma das duas grandes linhas de pesquisa em economia da educação (aspectos econômicos dos sistemas educacionais). Apresentam-se a evolução histórica, o estado atual do debate e as perspectivas de desenvolvimento das teorias econômicas de oferta de educação, abarcando-se o período compreendido entre o início da década de 1960 e as contribuições mais recentes. Argumenta-se que as teorias tradicionais de economia da educação (capital humano e sinalização) não deram tratamento adequado ao lado da oferta da educação. Mais tarde, os conceitos e o instrumental da microeconomia da firma foram mobilizados a fim de se tentar mapear a "tecnologia de produção de educação". A abordagem das funções de produção de educação, baseadas inicialmente apenas em insumos monetários, não foi suficiente para que se apreendesse toda a complexidade envolvida no processo de provisão de educação. Uma análise de artigos mais recentes revela três caminhos promissores para o desenvolvimento das teorias de oferta de educação: (i) incluir insumos não monetários às funções de produção; (ii) levar em consideração aspectos institucionais e organizacionais do sistema educativo; e (iii) aprimorar as técnicas econométricas de estimação das funções de produção. Por fim...

Technical and economic optimum in feedlot cattle

Rebollar-Rebollar,S.; Posadas-Domínguez,R. R; Hernández-Martínez,J.; Rojo-Rubio,R.; González-Razo,F. J.; Guzmán-Soria,E
Fonte: Universidad Autónoma de Yucatán, Facultad de Medicina Veterinaria Publicador: Universidad Autónoma de Yucatán, Facultad de Medicina Veterinaria
Tipo: Artigo de Revista Científica Formato: text/html
Publicado em 01/08/2011 EN
Relevância na Pesquisa
45.86%
The beef cattle producers in the southern zone of the State of Mexico generally do not carry out adequate market planning of their finished steers. In addition, they lack technical and administrative management in their productive units, focused on the use of efficient input, which has prevented them from maximizing their monetary profits. The present investigation was made to estimate the technical (TOL) and economic optimum levels (EOL) of feedlot beef cattle, using two cubic production functions with decreasing marginal yields. One hundred steers of Bos Taurus x Bos indicus were used, with Live Weight at the start of fattening of 290 ± 15 kg, age 21 to 24 months, fattened in feedlots during 93 days consuming a totally mixed diet (Crude protein: 133.33, FDN: 237.44, FDA 114.33 g/kg DM and 2.62 Mcal/kg of DM of metabolizable energy) To estimate both functions (TOL and EOL), weight gain was considered as independent variable. For the first production function, feed intake was taken as independent variable and in the second function, time defined in days. For the first production function the TOL was 475.04 and the EOL was 473.94 kg Live Weight; with a daily feed intake of 12.58 and 12.36 kg/day. For the second production function the TOL was 475.01 and the EOL was 460.21kg of Live Weight...

Relationships between ecological infrastructure and the economy: The case of a fishery

Crafford,Jacobus G.; Hassan,Rashid M.
Fonte: South African Journal of Science Publicador: South African Journal of Science
Tipo: Artigo de Revista Científica Formato: text/html
Publicado em 01/08/2014 EN
Relevância na Pesquisa
45.74%
The Millennium Ecosystem Assessment identified the regulating services as amongst the least understood but potentially most valuable services offered by ecosystems. This lack of understanding of regulating services has been a major reason for the overexploitation and degradation of ecosystems. The value of regulating services is best determined through an economic production function approach, which derives the value of regulating services as intermediate inputs into other economic goods and services. We used existing scientific knowledge and data sourced from existing scientific databases and studies to develop and demonstrate empirical production functions that measure relationships between ecological infrastructure and the economy in fisheries in KwaZulu-Natal, along the east coast of South Africa. We applied econometric analyses - a technique that allows for evidence-based analysis of observed data, based on existing scientific knowledge. Our work demonstrates that existing scientific databases may contain useful evidence of relationships between ecological infrastructure and the economy, and that decisions need not always wait for the results of controlled experiments.