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51.
Daniil Ryabko 《Statistics》2013,47(1):121-128
Given a discrete-valued sample X1, …, Xn, we wish to decide whether it was generated by a distribution belonging to a family H0, or it was generated by a distribution belonging to a family H1. In this work, we assume that all distributions are stationary ergodic, and do not make any further assumptions (e.g. no independence or mixing rate assumptions). We would like to have a test whose probability of error (both Types I and II) is uniformly bounded. More precisely, we require that for each ? there exists a sample size n such that probability of error is upper-bounded by ? for samples longer than n. We find some necessary and some sufficient conditions on H0 and H1 under which a consistent test (with this notion of consistency) exists. These conditions are topological, with respect to the topology of distributional distance.  相似文献   
52.
The 7-item adult version of the Personal Wellbeing scale (Cummins et al. Social Indic Res 64:159?C190, 2003) was administered to two samples of adolescents aged 12?C16 in Brazil (N?=?1,588) and Spain (N?=?2,900), and to a sample of adolescents aged 14?C16 in Chile (N?=?843). The results obtained were analyzed to determine its psychometric characteristics when used with adolescents in the three different countries and to check whether two additional items would improve its qualities. Results reveal that the new PWI-9 version worked well with the adolescents in the three countries, improving some of the qualities of the PWI-7. One of the added items, satisfaction with oneself, appears to be a major contributor to unique explained variance when regressed on the single-item of overall life satisfaction (OLS). The model we present using structural equations shows good fit statistics for the factor structure, with both 7 and 9 items. Separate in-country analyses demonstrate that cultural context has a strong influence on correlations and saturations between the studied variables and also on the explained variance. Probably related to this fact, the Model fit structure is good in Brazil (with a low PWI variance accounted for by its predictors) and Spain (medium), but rather modest in Chile, where data show a high proportion of the PWI variance accounted for by its predictors. However, a multi-group factor analysis among the three countries restricting saturations to 1 in each country in order to make data comparable across countries still show a good fit of the proposed model for both PWI-7 and PWI-9.  相似文献   
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Skew‐symmetric families of distributions such as the skew‐normal and skew‐t represent supersets of the normal and t distributions, and they exhibit richer classes of extremal behaviour. By defining a non‐stationary skew‐normal process, which allows the easy handling of positive definite, non‐stationary covariance functions, we derive a new family of max‐stable processes – the extremal skew‐t process. This process is a superset of non‐stationary processes that include the stationary extremal‐t processes. We provide the spectral representation and the resulting angular densities of the extremal skew‐t process and illustrate its practical implementation.  相似文献   
55.
We examine firms' propensity to adapt their R&D collaboration portfolio by establishing new types of R&D collaboration with different kinds of partners (suppliers, customers, competitors and universities & public research institutions). We argue that existing R&D collaboration with one of the two value chain partners (suppliers or customers) is associated with the formation of new R&D collaboration with the other value chain partner to ensure temporal alignment in innovation within the value chain. In contrast, issues related to governance and unintended knowledge spillovers suggest that ‘horizontal’ R&D collaboration with competitors only spurs R&D collaboration with other partner types if such competitor R&D collaboration has been discontinued earlier (‘delayed temporal alignment’). We posit that persistent prior R&D collaboration with institutional partners is an antecedent to the establishment of new R&D collaboration with industrial partners, and that discontinuation of a particular type of R&D collaboration is likely to lead to a restart of such R&D collaborative effort. Strong prior innovative performance is expected to increase the probability that firms establish R&D collaborations with new partner types, except for R&D collaboration with competitors, since the most innovative firms may fear leakage of proprietary knowledge to rivals. We find broad support for these predictions in a large panel of Spanish innovating firms (2004–2011). Our findings highlight that it is not just the configuration of R&D collaborations with existing partner types that predicts tie formation with new partner types, but also the intertemporal pattern of prior R&D collaboration and managerial discretion provided by past innovation success.  相似文献   
56.
ABSTRACT

The academic Marxism of the 20th century has shied away from this responsibility, preferring relatively comfortable staying within the walls of universities. Unlike these academic thinkers Samir Amin was one of the few who did not accept this situation. He never considered himself merely a theorist: connection to praxis was vital for him. From this perspective he advocated a project of Fifth International to address sharp and systemic crisis afflicting leftist movements. Each new stage of the evolution of capitalism requires a corresponding transformation of the anti-capitalist forces. Nevertheless, a new political alternative can’t be constructed artificially. It can only gradually emerge out of collective experience of different struggles.  相似文献   
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58.
A firm's reputation is an important intangible asset, because of its potential for value creation. The authors explore non‐monetary and monetary outcomes of customer‐based corporate reputation (CBR) and hypothesize that commitment serves as a partial mediator, while service context risk is a moderator, of these relationships. Using a large sample of service customers who evaluated the reputation of service firms in four service categories, the results show that (1) commitment partially mediates the relationship between CBR and most of the outcome variables, and (2) service provider selection risk moderates these relationships, such that reputation has a stronger effect on several non‐monetary outcomes for higher‐risk services and commitment has a stronger effect for lower‐risk services, consistent with a dual‐processing framework explanation. The authors discuss the theoretical and managerial implications.  相似文献   
59.
In politics and business the special role of innovative businesses whose research and development activities expedite technological progress has received steady attention. Especially small and medium sized businesses (SMEs) have initiated promising innovation projects. However, when analysing these projects our research must take into account that SMEs cannot be viewed as a homogeneous business category. Moreover, financing their innovations, SMEs are subject to unique issues. To shed light on these problems, this study will develop an index measuring degrees of innovation. It allows the 171 sample companies to be categorised into three groups: non-innovative, moderately innovative or highly innovative. A multinomial logistic regression is used to examine the quality of this typology. In addition, group-specific differences in the financing mix are demonstrated. Finally, from a theoretical point of view, the implications of the pecking order theory are basically validated. On the other hand, the concept of the financial growth cycle does not deliver satisfactory results.  相似文献   
60.
Survey data show that for Russians the most heinous crimes are serial murder, rape of minors, and premeditated murder, and these are the crimes for which they most often demand the death penalty. Four out of five say the Russian system of justice is guilty of mistakes often and very often, yet almost half of Russians are in favor of reinstituting and expanding the practical imposition of the death penalty  相似文献   
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