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131.
It has been found that for a wide range of industrial products the unit prices and costs decrease by a constant percentage when production volume doubles—this is called the experience effect. This unit price behaviour is also observed for certain classes of basic agricultural products. As international market competition increases, price behaviour differences among countries may lead farmers, their organizations and governments to better understand what are the causes of the differences so that they can maintain and improve their competitive position internationally.  相似文献   
132.
This paper delineates general validity and research questions that are underlying an ongoing program of research pertaining to the Early Development Instrument (EDI, Janus and Offord 2007), a population-level measure, on which teachers rate kindergarten children’s developmental outcomes in the social, emotional, physical, cognitive, and communicative domains. It describes the large-scale research projects that are using the EDI to measure children’s developmental outcomes for entire populations (e.g., provinces, cities). Given the uniqueness of the EDI’s use as monitoring tool, or social indicator, for children’s developmental health at an early age, we spell out the opportunities and challenges that these projects provide with regard to validation research. The article sets the stage for the special issue, as it is dedicated to showcase the different aspects of the conceptual, theoretical, and empirical validation research as well as the collaborative community-based projects that are currently being undertaken with respect to the EDI.  相似文献   
133.
The purposes of this paper are to highlight the foundations of multilevel construct validation, describe two methodological approaches and associated analytic techniques, and then apply these approaches and techniques to the multilevel construct validation of a widely-used school readiness measure called the Early Development Instrument (EDI; Janus and Offord 2007). Validation evidence is presented regarding the multilevel covariance structure of the EDI, the appropriateness of aggregation to classroom and neighbourhood levels, and the effects of teacher and classroom characteristics on these structural patterns. The results are then discussed in the context of the theoretical framework of the EDI, with suggestions for future validation work.  相似文献   
134.
Consider strategic risk‐neutral traders competing in schedules to supply liquidity to a risk‐averse agent who is privately informed about the value of the asset and his hedging needs. Imperfect competition in this common value environment is analyzed as a multi‐principal game in which liquidity suppliers offer trading mechanisms in a decentralized way. Each liquidity supplier behaves as a monopolist facing a residual demand curve resulting from the maximizing behavior of the informed agent and the trading mechanisms offered by his competitors. There exists a unique equilibrium in convex schedules. It is symmetric and differentiable and exhibits typical features of market‐power: Equilibrium trading volume is lower than ex ante efficiency would require. Liquidity suppliers charge positive mark‐ups and make positive expected profits, but these profits decrease with the number of competitors. In the limit, as this number goes to infinity, ask (resp. bid) prices converge towards the upper (resp. lower) tail expectations obtained in Glosten (1994) and expected profits are zero.  相似文献   
135.
Abstract. We analyse the efficiency of schooling choices in a wage‐posting search equilibrium model with on‐the‐job search. The workers have multidimensional skills and the search market is segmented by technology. Education determines the scope — or adaptability— of individual skills. Individuals obtain schooling to leave unemployment more quickly and to climb the wage ladder rapidly through job‐to‐job mobility — that is, to speed up job shopping. Education reduces firms’ monopsony power in the wage determination by improving workers’ mobility. As a result, the wage distribution shifts rightward with aggregate schooling. However, the ratio of vacant jobs to job seekers also falls in each sector. Either one or the other externality may dominate, implying, respectively, under‐ or over‐education. A combination of minimum wage and schooling fee can decentralize the efficient allocation.  相似文献   
136.
The digitalization of the economy can be interpreted as an industrial revolution, a series of technological innovations associated with new practices and new business models. As for previous industrial revolutions, a phase involving the destruction of existing systems and structures is driving a profound transformation of the world of work and the development of new sectors of activity and new jobs, including changes in the labour market and in the types of jobs created. This puts into question the position of the middle classes, and presents new challenges for social protection. This article seeks to understand the impacts of digital technology on the economy and employment, including the phenomena of labour market polarization. It describes the new forms of employment and work and analyses the social risks and the likely ramifications for the middle classes in the digital age. In turn, new possibilities for social protection in the digital age are discussed. The article concludes that there is a need to re‐evaluate jobs that involve the provision of personal and care services, including to support social investment, to strengthen the future prospects of the weakened middle classes.  相似文献   
137.
This analysis of the EU's influence on the future of national welfare states points out three distinct phases in the interactions between the building of Europe and of welfare states. During a phase of expansion (1950s-1970s), European authorities were building a common market while allowing member states that were lagging behind in welfare to catch up. During a second phase of conflict (1980s-1990s), advances in the economic construction of Europe caused tensions to flare up with social policies inherited from the past. During a third phase (starting in the late 1990s), EU authorities have been trying to reconcile economic policies with new social policies. To analyze each phase, we must take into account both the EU initiatives capable of having a direct or indirect impact on national welfare systems and the national welfare institutions and strategies that were adopted.  相似文献   
138.
This paper described the versatility of the multiple-indicator multilevel (MIML) model in helping to resolve four common challenges in studying growth using longitudinal data. These challenges are (1) how to deal with changes in measurement over time and investigate temporal measurement invariance, (2) how to model residual dependence due to the nested nature of longitudinal data, (3) how to model observed trajectories that do not follow well-known functions commonly discussed in the methodology literature (e.g., a linear or quadratic curve), and (4) how to decide which predictors are relatively more important in explaining individuals’ change over time. With an example of psychological well-being from the Wisconsin Longitudinal Study, we illustrated how the four methodological challenges can be resolved using the 3-phase MIML procedures and the Pratt’s importance measures.  相似文献   
139.
The biproportional apportionment problem (BAP) must be faced in many proportional electoral systems where seats must be allocated to parties within regions. BAP is a non-trivial optimization problem, and only sophisticated algorithms are currently available for solving it. The issue is: are they “writable” as an actual law? Citizens rightly demand simple, easy to understand, voting systems. The alternative, though, seems to have simple, but unsound electoral laws. We propose the following way out of this dilemma: leave to a mathematically sophisticated algorithm the task of producing an optimal apportionment, but attach to it a “certificate of optimality”, that is, describe a simple procedure whereby anybody can check, through some elementary operations, that the seat allocation output by the algorithm is indeed an optimal apportionment. We discuss one such certificate, based on the Max flow- min cut Theorem, relative to a parametric max flow method of ours for BAP.  相似文献   
140.
Several measurement assumptions were examined with the goal of assessing the validity of the Multidimensional Students’ Life Satisfaction Scale (MSLSS), a measure of adolescents’ satisfaction with their family, friends, living environment, school, self, and general quality of life. The data were obtained via a cross-sectional survey of 8,225 adolescents in British Columbia, Canada. Confirmatory factor and factor mixture analyses of ordinal data were used to examine the measurement assumptions. The adolescents did not respond to all the MSLSS items in a psychometrically equivalent manner. A correlated five-factor model for an abridged version of the MSLSS resulted in good fit when all negatively worded items and several positively worded items (the least invariant) were excluded. The abridged 18-item version of the MSLSS provides a promising alternative for the measurement of five life domains that are pertinent to adolescents’ quality of life.  相似文献   
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