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51.
This paper investigates the consequences of incorrectly modelling the investment outflow/benefit inflow relationship on estimates of the internal rate of return (IRR) prepared by using cash recovery rates (CRRs). The main result of this paper is that CRR-based estimates of the IRR will contain such bias if and only if either the duration of the assumed shape of the investment outflow/benefit inflow relationship is less than the duration of the true investment outflow/benefit inflow relationship for all rates of interest or the duration of the assumed shape of the investment outflowlbenefit inflow relationship is greater than the duration of the true investment outflowlbenefit inflow relationship for all rates of interest. This result is then applied to the case where both the true and the assumed shape of the investment outflow/benefit inflow relationships have benefit inflows that change exponentially over time. It is shown that if the exponential rate of change is mis-specified the resulting CRR-based estimate of the IRR will contain systematic bias monotonically related to the rate of growth.  相似文献   
52.
We use a vertical product differentiation model under partial market coverage to study the social welfare optimum and duopoly equilibrium when convex costs of quality provision are either fixed or variable in terms of production. We show the following new results. First, under fixed costs, the social planner charges a uniform price for the single variant that just covers costs of quality provision. Like the duopoly equilibrium, this socially optimal pricing entails a partially uncovered market, but a smaller share of the market is served compared with the duopoly equilibrium. Second, for the variable cost case, it is socially optimal to provide both high‐ and low‐quality variants, but market shares need not be equal. This differs from the result in fully covered markets. Third, in the duopoly equilibrium, the quality spread is too wide under variable costs relative to the social optimum. Under fixed costs, the duopoly produces two variants, but quality is too low relative to the social optimum, which has only one variant.  相似文献   
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Employment,schooling and productivity growth   总被引:1,自引:1,他引:0  
Summary This paper presents an empirical analysis of labour demand and labour productivity growth in The Netherlands. Assuming an aggregate production function with as factors capital and 3 types of labour, distinguished by educational attainment, cost minimization leads to a set of 3 labour demand relations to be estimated on time series data. Using the estimates and the implied elasticities, aggregate labour productivity growth is decomposed into factor substitution, autonomous factors, labour time shortening, economies of scale, utilization rates and the increased educational level of the working population. The contributions of substitution, utilization rates and education appear to be substantial, notably in the seventies.

List of symbols

Variables a i Efficiency index of skill leveli - C production - h i working-time index for skill leveli - g i steady-state growth rate of skill leveli - K capital stock - L i employment volume of skill leveli - L i * desired level of labour skill leveli - p output price - p * desired output price - s i * long-run static labour shares in the production value - p k rental price of capital - P index of total factor productivity - P l index of labour productivity - u i utilization rate of skill leveli - u k utilization rate of capital - w i wage rate for skill leveli - y production volume - y yij Hicks partial elasticities of complementarity - i steady-state cost share of skill leveli - k Bk steady-state cost share of capital - f lf highest level price index in cost function nesting - g 4 intermediate level price index in cost function nesting - h 4 lowest level price index in cost function nesting - i steady-state relative wage share of skill leveli - ij Allen partial elasticities of substitution Parameters d i l adjustment speed of skill leveli - d p price adjustment speed - M mark-up on marginal costs - scale elasticity of production - i distribution parameter in cost function,i = 3, g - i distribution parameter in cost function,i = k, h - i distribution parameter in cost function,i =1, 2 - i autonomous labour productivity growth for skill leveli - i cost share of skill level in base year - f production cost index in base year - i hours elasticity in labour efficiency index - group elasticity of substitution betweenL 3 and (K, (L 1,L 2)) - g Og group elasticity of substitution betweenK and (L 1,L 2) - h 6h group elasticity of substitution betweenL 1 andL 2 We would like to thank B. Downey, G.M.M. Gelauff, A. Nieuwenhuis, J.M.M. Ritzen, J.C. Siebrand and an unknown referee for helpful comments on earlier drafts.  相似文献   
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The South African research community which undertakes all research activity in the social and natural sciences, with and without state and corporate sponsorship, draws its membership mainly from the dominant social group. In this country, the dominant group is both economically and racially determined. Consequently, the white minority dominates the research community and intellectual discourse as it does other socio‐economic and political spheres of society. This situation guarantees the constant reproduction and perpetuation of the social relations of racial domination.

As an agent that generates knowledge and new ideas, research as an academic and intellectual tool of enquiry is an instrument of social control, producing new concepts, language and theoretical abstractions which are not accessible to those outside its multi‐farious disciplines. Insofar as the largest proportion of practitioners of these specialised disciplines is drawn from the dominant group, research has itself become a pivotal part of the dominant ideology. Its role is inevitably and inextricably bound up with the processes of systematic reproduction of the relations of domination.

The aim of this viewpoint is therefore to explore various ways in which research bodies and intellectual discourse in general in South Africa can be deracialised and be made more representative of the social make‐up of society.  相似文献   

58.
Richman LS 《Fortune》1992,126(3):34-40
Many more than ever face the crises of childhood: violence, drugs, bad schools, poverty, divorce, or two parents at work. And no one seems to care.  相似文献   
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60.
This analysis investigates the assertion that the baby-boom cohorts, by virtue of their large size and new lifecourse redistribution tendencies, are likely to initiate significant shifts in the distribution of the elderly population as these cohorts enter into the 65-and-older age categories. The author contends that cohorts' pre-elderly lifecourse migration patterns should be incorporated into studies of elderly population distribution shifts. 2 questions are addressed: will the new lifecourse migration patterns provide for a more deconcentrated redistribution of the baby-boom cohorts, both prior to and after their entry into the elderly age categories, than the lifecourse migration patterns followed by earlier cohorts; and will the new lifecourse distribution pattern lead, in the long run, to a significantly more deconcentrated distribution of the elderly population. The examination of these 2 questions focuses, largely, on redistribution across 9 broad regional and metropolitan area groupings defined on the basis of 3 census regions -- the North (combining the Northeast and Midwest census regions), the South, and the West -- and 3 categories of metropolitan status -- large metropolitan areas (those with 1980 populations exceeding 1 million), other metropolitan areas, and nonmetropolitan areas. The comparison of "new" versus "old" lifecourse migration patterns contrasts the census-based age-specific migration stream rates, registered over the 1975-80 period, with those registered over the 1965-70 period. Given the sharp and broad-based shift toward deconcentrated redistribution which characterized practically all segments of the population during the 1970s, it is assumed that the age-specific migration patterns observed over the 1975-80 period approximate the more deconcentrated redistribution tendencies which will be adopted by the baby-boom cohorts (and their successors) over the remainder of their lifecourse. The 1965-70 net migration rates point up the aggregate redistribution implications associated with the "old" lifecourse migration stream patterns. Among the rates for North large metropolitan areas, the only positive net migration is observed for the 25-29 age category; the greatest net outmigration rate is shown for the 65-69 age category. The rates for South nonmetropolitan areas are negative for all age categories under age 55, and most accentuated outmigration is shown during the young-adult years. The positive net migration exhibited for the older adult and post retirement ages reflects the low outmigration rates from nonmetropolitan areas during these ages and the slight peaking of immigration for these years. The results of this analysis imply that more attention should be devoted to migration, over the entirety of the lifecourse, in future studies of population redistribution.  相似文献   
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