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Public Choice - It is well established in the literature that the number of interest group organizations varies across countries and states, with economic freedom and other institutional factors...  相似文献   
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The influence of childhood contexts on adult blood pressure is an important yet understudied topic. Using a developmental perspective, this study examines the association between neighborhood socioeconomic disadvantage in early childhood (0–5?yrs), middle childhood (6–12?yrs) and adolescence (13–18?yrs) on subsequent blood pressure in young adulthood. Data were from 263 college students (52% Black; Mage?=?19.21 years) and neighborhood socioeconomic disadvantage was measured using a tract-level Area Deprivation Index. Neighborhood disadvantage in early childhood was significantly associated with diastolic blood pressure and explained 22% of the race difference between Black and White adults. The findings are consistent with the notion that early childhood may be a sensitive period for the effects of neighborhood disadvantage on blood pressure.

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Underinvestment in Public Good Technologies   总被引:2,自引:0,他引:2  
Although underinvestment phenomena are the rationale for government subsidization of research and development (R&D), the concept is poorly defined and its impact is seldom quantified. Conceptually, underinvestment in industrial R&D can take the form of either a wrong amount or a suboptimal composition of R&D investment. In both cases, R&D policy has not adequately modeled the relevant economic phenomena and thus is unable to characterize, explain, and measure the underinvestment. Four factors can cause systematic underinvestment in R&D-intensive industries: complexity, timing, existence of economies of scale and scope, and spillovers. The impacts of these factors vary in intensity over the typical technology life cycle, so government policy responses must be managed dynamically. In addition to understanding the causes of underinvestment in R&D, the magnitude of the deficiency relative to some “optimum” must be estimated to enable a ranking of technology areas with respect to expected net economic benefits from a government subsidy. Project selection criteria must therefore be based on quantitative and qualitative indicators that represent the nature and the magnitude of identified market failures. The major requirement for management of R&D policy therefore is a methodology that regularly assesses long-term expected benefits and risks from current and proposed R&D portfolios. To this end, a three-stage process is proposed to effectively carry out R&D policy analysis. The three stages are (1) identify and explain the causes of the underinvestment, (2) characterize and assess the investment trends and their impacts, and (3) estimate the magnitude of the underinvestment relative to a perceived optimum in terms of its cost to the economy. Only after all three stages of analysis have been completed can the underinvestment pattern be matched with the appropriate policy response.  相似文献   
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