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21.
In 2015, the United Nations (UN) issued probabilistic population projections for all countries up to 2100, by simulating future levels of total fertility and life expectancy and combining the results using a standard cohort component projection method. For the 40 countries with generalized HIV/AIDS epidemics, the mortality projections used the Spectrum/Estimation and Projection Package (EPP) model, a complex, multistate model designed for short-term projections of policy-relevant quantities for the epidemic. We propose a simpler approach that is more compatible with existing UN projection methods for other countries. Changes in life expectancy are projected probabilistically using a simple time series regression and then converted to age- and sex-specific mortality rates using model life tables designed for countries with HIV/AIDS epidemics. These are then input to the cohort component method, as for other countries. The method performed well in an out-of-sample cross-validation experiment. It gives similar short-run projections to Spectrum/EPP, while being simpler and avoiding multistate modelling.  相似文献   
22.
The longstanding focus of elite athletes on top sports entails disadvantages hampering their later entry to the world of work. In order to successfully contribute their outstanding personality traits to a later job, athletes are thus particularly required to care for their employability. Contributing to this, the author carried out a competency balancing with top athletes. This coaching method significantly decreased the athletes’ need for self-information. Evaluation further showed indications of increased clarity and certainty of occupational goals as well as work satisfaction.  相似文献   
23.
A simple connected graph G with 2n vertices is said to be k-extendable for an integer k with \(0<k<n\) if G contains a perfect matching and every matching of cardinality k in G is a subset of some perfect matching. Lakhal and Litzler (Inf Process Lett 65(1):11–16, 1998) discovered a polynomial algorithm that decides whether a bipartite graph is k-extendable. For general graphs, however, it has been an open problem whether there exists a polynomial algorithm. The new result presented in this paper is that the extendability problem is co-NP-complete.  相似文献   
24.
We revise existing and introduce new mixed-integer programming models for the Multiprocessor scheduling problem with communication delays. The basis for both is the identification of two major modeling strategies one of which can be considered ordering-based, and the other assignment-based. We first reveal redundancies in the encoding of feasible solutions found in present formulations and discuss how they can be avoided. For the assignment-based approach, we propose new inequalities that lead to provably stronger continuous relaxations and better performance in practice. Moreover, we derive a third, novel modeling strategy and show how to more compactly linearize assignment formulations with quadratic constraints. In a comprehensive experimental comparison of representative models that reflect the state-of-the-art in terms of strength and size, we evaluate not only running times but also the obtained lower and upper bounds on the makespan for the harder instances of a large scale benchmark set.  相似文献   
25.
Klassen messen     
The article investigates whether Austrian sociological research empirically addressed social class conceptions between 1945 and 1990. Contrary to the German reception, we find that, indeed, during the whole period scientific publications analyzed social relations and social change from a class perspective with an empirical approach. We embed this research in its historical context in order to work out the implicit explanations given concerning the existence of social inequalities. Moreover, we work out if post-World War II Austrian class analysis did link its work to the Austro-Marxist tradition that flourished between the two World Wars. The empirical focus of the article lies on scientific publications with an empirical approach to social classes and social change.  相似文献   
26.
International coopetition has rarely been studied in relation to innovation. Further exploration of effects of international coopetition, i.e. the pursuit of simultaneous cooperation and competition, on a firm’s innovation performance is especially important as such a relationship is challenging with a high propensity to fail. This observation formed the point of departure for this study, which aims to increase the understanding of the effects of international coopetition on firm innovativeness and how these effects are conditioned on the magnitude of the organizational adjustments a firm introduces. We use an unbalanced panel of 9839 firms that participated in four waves of the Swedish Community Innovation Survey between 2008 and 2014 as our empirical base. We illustrate that firms that cooperate with competitors internationally are more likely to exhibit higher propensity to introduce radical innovations, yet this effect is conditioned upon the magnitude of organizational adjustments. Overall, our study contributes to the understanding of the implications of international coopetition and what a firm needs to benefit from it.  相似文献   
27.
Schumpeterian market disequilibrium marked by entrepreneurial entry and incumbent exit has long held an important place in management literature. The extant literature has overwhelmingly championed the newcomer, despite incumbents' obvious advantages in resources, experience and market knowledge. The current research provides evidence for the effectiveness of the incumbent's strategy of capability enhancement (along an established technological trajectory) while responding to radical technological innovations. We develop a cognitive process model that integrates managerial cognition with capability development and deployment views, depicting the dynamics of the incumbent's capability enhancement process. We analyze the cognitive drivers of organizational actions in all stages (rigidity, triggering event, and capability renewal) and elucidate the role of top management cognition in the processes of detecting and correcting errors in a strategic course of action. We ground our model in the case of a cork-stopper industry veteran's decline as corks ceded ground to screw tops and other stoppers in the wine industry. How a major company fought back in response to the emergence of these, in the industry context, radical technological innovations, provides the basis for our narrative. The proposed theoretical model contributes to literature on technology management (with regard to incumbent strategies in response to radical innovation threats) as well as the role of cognition in strategy (providing an explanation of the cognitive underpinnings of capability development).  相似文献   
28.
This paper examines the determinants of base pay and total incentive compensation packages of CEOs of biopharmaceutical firms that have recently gone public, and whether human capital and agency factors affect the market’s response to the initial public offering. We find that in terms of net proceeds, the IPO market appears to reward the firms that have founder-CEOs and CEOs with higher incentive compensation. CEOs with prior venture capital experience are associated with receiving higher incentive compensation, while CEOs with a greater ownership interest in the firm receive lower incentive compensation but higher salaries. CEOs of firms with a greater percentage of insiders are associated with lower salaries. The results should add to our understanding related to human capital and agency theories, as well as help firms and investors better understand and structure CEO compensation.  相似文献   
29.
Yana Kucheva 《Demography》2018,55(2):617-642
Despite abundant evidence about the effect of children’s socioeconomic circumstances on their transition to adulthood, we know much less about the effect of social policy programs aimed at poor families with children in facilitating how and when children become adults. This issue is particularly important for the U.S. federal subsidized housing program given its long history of placing subsidized units in some of the poorest and most racially segregated neighborhoods. Using counterfactual causal methods that adjust for the length of receipt of subsidized housing, I estimate the effect of subsidized housing on teenage parenthood, household formation, and educational attainment. I find that the subsidized housing program has either null or positive effects on the transition to adulthood and that these effects vary by both race and gender. These results underscore the importance of considering whether social programs have differential effects on the life chances of individuals based on both race and gender.  相似文献   
30.
Journal of Nonverbal Behavior - Age-related deficits are often observed in emotion categorization tasks that include negative emotional expressions like anger, fear, and sadness. Stimulus...  相似文献   
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