The synchronization process inherent to the Bitcoin network gives rise to an infinite-server model with the unusual feature that customers interact. Among the closed-form characteristics that we derive for this model is the busy period distribution which, counterintuitively, does not depend on the arrival rate. We explain this by exploiting the equivalence between two specific service disciplines, which is also used to derive the model’s stationary distribution. Next to these closed-form results, the second major contribution concerns an asymptotic result: a fluid limit in the presence of service delays. Since fluid limits arise under scalings of the law-of-large-numbers type, they are usually deterministic, but in the setting of the model discussed in this paper the fluid limit is random (more specifically, of growth-collapse type). 相似文献
This paper examines the effects of exchange rate depreciation to the U.S. economy in a factor‐augmented vector autoregression model using monthly data of 148 variables for the post–Bretton Woods period of 1973–2017. Exchange rate shock is identified to reflect exogenous disturbances to the foreign exchange market, and movements in exchange rate that are not accounted for by changes in the U.S. monetary policy. We find that depreciation is expansionary and inflationary to the broad U.S. economy, the current account improves over time conforming to the J‐curve theory, and monetary policy is leaning against the wind. (JEL E3, E5, F31, F32, F41) 相似文献
Using seven waves of data from the Hispanic Established Population for the Epidemiologic Study of the Elderly (1993–2011), this study applies multiphase growth models to examine changes in limitations with activities of daily living (ADL) across widowhood experience among 385 older adults of Mexican descent. This study also investigates the implications of demographic characteristics, health, socioeconomic status, living arrangements, and social involvement. ADL limitations increased pre-widowhood, were at higher levels immediately before and especially during the transition to widowhood, and increased at a steeper rate post-widowhood. Age and partially depressive symptoms accounted for these trends in ADL limitations pre-widowhood and to a lesser extent during the transition to widowhood and post-widowhood. Older age, being female, chronic conditions, financial strain, lower educational attainment, coresidence with children and others, and less frequent church attendance were risk factors for higher levels of and greater increases in these functional limitations throughout widowhood experience. 相似文献
When working with clients in another language, having culturally relevant and properly translated clinic materials is vital to effective clinical practice. Not having them presents a barrier for bilingual therapists and their clients. This paper reviews common translation methods and introduces a multi‐level, community‐based approach for translating clinic materials for non‐English speaking clients. Informed by decolonizing practices, this five‐tier method includes members from the target community as cultural brokers to verify the accuracy and nuances of language for their cultural group, as well as a constant comparative method to ensure methodological rigor in the process of inclusion. We present community member's feedback and recommendations, as well as discuss advantages and challenges of using this collaborative culturally responsive translation method. 相似文献
The current study examined the role of hypothalamic‐pituitary‐adrenal reactivity (a physiological indicator of stress) in early infancy as a mediator of the relationship between maternal postpartum depression and toddler behavior problems. Participants were 137 at‐risk mothers and their children participating in a longitudinal study of intergenerational transmission of risk. Mothers’ depression was measured five times during the infants’ first 18 months. Infant cortisol was collected during a social stressor (the still‐face paradigm) when infants were 6 months old, and mothers reported on toddlers’ internalizing and externalizing symptoms at 18 months. Among this sample of high‐risk mother–infant dyads, early postpartum depression predicted atypical infant cortisol reactivity at 6 months, which mediated the effect of maternal depression on increased toddler behavior problems. Clinical implications are discussed. 相似文献
Urban Ecosystems - Urbanization-induced habitat loss and alteration causes significant challenges for the survival of many species. Identifying how species respond to urbanization can yield... 相似文献
Urban Ecosystems - Urban streams provide important ecosystem services to cities’ population, from the maintenance of urban biodiversity, temperature, humidity and air quality to improving... 相似文献
The European Union’s (EU) Youth Guarantee aims to improve the labour market situation of young people. Rather than prescribing a uniform policy model, it acknowledges that supportive measures need to align with national, regional and local circumstances. It thus seeks to promote mutual policy learning through the open method of coordination. As an innovative measure, the EU has deployed funding programmes to support the domestic measures related to the Youth Guarantee. We therefore examined in this study whether this mix of recommendations and financial incentives has entailed a convergence of member state policies. Our analysis of policy outputs for the period 2007?2014 yields a mixed empirical picture. There is catching‐up convergence regarding policies’ sectoral coverage but increasing divergence concerning the number of adopted policy instruments. The first two years of financial incentives did not produce any effect on enhancing policy experimentation among less active member states. We offer an optimistic and a pessimistic interpretation of these findings. 相似文献
This paper uses recent multidimensional well-being measurements to examine multidimensional well-being and inequality across the European regions in 2000 and 2014 with the use of eleven well-being indicators from the OECD Better Life Index. We use generalized mean aggregation method with alternative parameters to allow different substitutability and complementarity levels between well-being dimensions, which range between perfect substitutability and some degree of complementarity between the dimensions, to examine well-being and inequality across the European regions. Accounting for the interactions between the well-being dimensions matters for the multidimensional well-being and inequality across the European regions. The results show that the multidimensional well-being across the European regions are relatively lower when the dimensions are more seen as complements compared to the case when they are considered to be perfect substitutes. Furthermore, there is also a higher degree of multidimensional inequality across the European regions when the dimensions are considered to have some complementarity. Changes in well-being dimensions between 2000 and 2014 indicates that multidimensional well-being improved and inequality decreased in the personal and community well-being categories, but remained unchanged in material well-being category across the European regions irrespective of interaction levels between well-being dimensions. Policy implications of these multidimensional well-being indices are also evaluated by using these indices to determine the eligible regions for the European Union structural funds where the number eligible regions shows some variation depending on whether the dimensions are perfect substitutes or more of complements.
This paper shows that altruism may be beneficial in bargaining when there is competition for bargaining partners. In a game
with random proposers, the most altruistic player has the highest material payoff if players are sufficiently patient. However,
this advantage is eroded as the discount factor increases, and if players are perfectly patient altruism and spite become
irrelevant for material payoffs. 相似文献