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1.
LetX 1,X 2, …,X n(n ? 2) be a random sample on a random variablex with a continuous distribution functionF which is strictly increasing over (a, b), ?∞ ?a <b ? ∞, the support ofF andX 1:n ?X 2:n ? … ?X n:n the corresponding order statistics. Letg be a nonconstant continuous function over (a, b) with finiteg(a +) andE {g(X)}. Then for some positive integers, 1 <s ?n $$E\left\{ {\frac{1}{{s - 1}}\sum\limits_{i - 1}^{s - 1} {g(X_{i:n} )|X_{s:n} } = x} \right\} = 1/2(g(x) + g(a^ + )), \forall x \in (a,b)$$ iffg is bounded, monotonic and \(F(x) = \frac{{g(x) - g(a^ + )}}{{g(b^ - ) - g(a^ + )}},\forall x \in (a,b)\) . This leads to characterization of several distribution functions. A general form of this result is also stated.  相似文献   

2.
We present a new type of Artificial Neural Networks: the Self-Reflexive Networks. We utter the theoretical presuppositions; their dynamics is analogous to the one ascribed to autopoietic systems: self-referentiality, unsupervised learning and unintentionally cooperative and contractual activities of their own units. We also hypothesize a new concept of perception. We present the basic equations of Self-Reflexive Networks, new concepts as the one of dynamic target, of Re-entry with dedicated and fixed connections, of Meta-Units. Therefore, we experiment a specific type of Self-Reflexive Networks, the Monodedicated, within the interpretation of a toy-DB and we have hinted at other already made experimentations, experimentations in process and planned experimentations. From the applicative work that we present a few specifics and novelties of this type of Neural Networks emerge:
  1. the capability of answering to complex, strange, wrong or not precise questions, through the same algorithms through which the learning phase took place.
  2. the capability of spontaneously transforming their own learning inaccuracy in analogic capability and original self-organization capability.
  3. the capability of spontaneously integrate the models that it experienced in different moments in an achronical hyper-model.
  4. the capability of behaving as it had explored a decisions graph of large dimensions, both deeply and in extension. With the consequence of behaving as an Addressing Memory forself-dynamic Contents.
  5. the capability of always learning, rapidly and anyway, besides the complexity of the learning patterns.
  6. the capability of answering simultaneously from different points of view, behaving, in this case, as a network that builds more similarity models for each vector-stimulus that it receives.
  7. the capability of adjusting in a biunivocal way, each question to the consulting DB and each DB to the question that are submitted. The consequence of this fact is the continuous creation of new answering models.
  8. the capability of building during the learning phase, a weights matrix that provides a subconceptual representation of the bi-directional relations between each couple of input variables.
  9. the capability, through the Metaunits, to integrate in a unitary typology, nodes with different saturation speed and, therefore, with different memory: in fact, while the SR units are short memory nodes, since each new stumulus zeros the previous stimulus, the Metaunits memorize the SR different stimulus during time, functioning as an average length memory. This fact should confirm that the avarage length memory is of a different level from the immediate memory and that it is based only uponrelation among perceptive stimulus which are distributed in parallel and in sequence. In this context the weights matrix constitute the SR long term memory. And in this sense it will be opportune to think at a methodic through which the Metaunits can influence during time, the same weights matrix. In any case, in the SR there areservice nodes orfilter nodes andlearning nodes as if they were weights (the Metaunits).
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Long a site for incessant worry, revision or redemption, it is unclear what the ‘city' is today. Yet, in face of the near‐apocalyptic readjustments potentiated by human‐engineered global warming, there is an exigency about getting cities to function right. It is no wonder, then, that contemporary theories of cities and urbanization attempt to restore some common sense, to get to the heart of critical matters in a world where urbanization disrupts once‐normative assumptions about the nature of territory, scale and politics. But what is the nature of that ‘common sense'? How does one engage the very concrete efforts that constructed the city, with all the layers of physical and cultural memory that new regimes usually attempt to cover up, and all that the city does not show, either because its inhabitants are prohibited from paying attention or because whatever is considered normative or spectacular in city life has to get rid of the messy labor and politics that brought it about? Invoking blackness as an analytical method, these questions are addressed through thinking about how long histories of urban practices deployed by black residents of cities across the world might challenge and reinvent the sense of an urban commons.
‘Living just enough, just enough for the city…' Stevie Wonder (1973)
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5.
The literature on neighbor designs as introduced by Rees (Biometrics 23:779–791, 1967) is mainly devoted to construction methods, providing few results on their statistical properties, such as efficiency and optimality. A review of the available literature, with special emphasis on the optimality of neighbor designs under various fixed effects interference models, is given in Filipiak and Markiewicz (Commun Stat Theory Methods 46:1127–1143, 2017). The aim of this paper is to verify whether the designs presented by Filipiak and Markiewicz (2017) as universally optimal under fixed interference models are still universally optimal under models with random interference effects. Moreover, it is shown that for a specified covariance matrix of random interference effects, a universally optimal design under mixed interference models with block effects is universally optimal over a wider class of designs. In this paper the method presented by Filipiak and Markiewicz (Metrika 65:369–386, 2007) is extended and then applied to mixed interference models without or with block effects.  相似文献   

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In the paper, we consider the following problem: Let {πk} be a sequence satisfying 0πkΣ1 (k=1,…, N) and π=n.Tben, is there an unordered sampling design such that, for each k=1,…N, the inclusion probability of unit k is equal to π? It is shown that it can be solved by the straightforward application of the Minkowski-Farkas theorem.  相似文献   

8.
We study the house allocation problem with existing tenants: n houses (stand for “indivisible objects”) are to be allocated to n agents; each agent needs exactly one house and has strict preferences; k houses are initially unowned; k agents initially do not own houses; the remaining nk agents (the so-called “existing tenants”) initially own the remaining nk houses (each owns one). In this setting, we consider various randomized allocation rules under which voluntary participation of existing tenants is assured and the randomization procedure either treats agents equally or discriminates against some (or all) of the existing tenants. We obtain two equivalence results, which generalize the equivalence results in Abdulkadiroğlu and Sönmez (1999) and Sönmez and Ünver (2005).  相似文献   

9.
  • An increasing number of service organizations are developing thrift stores (or, second hand stores, charity shops) to raise resources to support their mission‐directed activities. Such stores seek donated merchandize…sell it …and use the proceeds to support their service efforts. The purpose of the study is to examine the processes by which thrift store donors: (a) determine that donation of pre‐owned merchandize is desirable, (b) get information about competing donation outlets, and (c) select which organization(s) are appropriate for their particular merchandize donation. A web survey was administered to assess these processes. The results will allow organizations to critically evaluate their existing thrift store practices against donor preferences in the interest of continuous improvement.
Copyright © 2009 John Wiley & Sons, Ltd.  相似文献   

10.
Let a1,…,an be a finite sequence of n real numbers. A subset {i1,…,ir} of the set {1,…,n } is called a balancing subset for a1,…,an if ai1 + … + air = 0. We discuss in this paper the maximum number of balancing subsets for given n.  相似文献   

11.
Online crowdfunding means relying on the Internet to seek financial support from the general public. In this paper, we examine success factors in the social capital networks of the top 5000 most funded projects in Kickstarter.com at the time of this study. We first look at how fundraisers and backers identify themselves with the projects they support in their own social networks. This is modelled using Facebook friends and Facebook shares, respectively, guided by social identity theory. Secondly, we use signalling theory to investigate crowdfunding success based on backers’ and fundraisers’ ability to engage in a forum, modelled using the number of comments between them, or with unilateral signals using the number of updates from the fundraiser. This study suggests that funders and backers who identify themselves with the projects in their own social networks are associated with greater pledge/backer ratio. We also find that projects where the fundraiser and its backers exchange more signals in a joint forum, but not signals delivered unilaterally by the fundraiser, have a greater pledge/backer ratio. These findings, based on a scalable quantitative study, highlight the importance of a multi-theory approach, advance social identity theory and signalling theory in the context of crowdfunding, and could be applied to online and normal entrepreneurship environments alike.  相似文献   

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The central concern of this paper is parameter heterogeneity in models specified by a number of unconditional or conditional moment conditions and thereby the provision of a framework for the development of apposite optimal m-tests against its potential presence. We initially consider the unconditional moment restrictions framework. Optimal m-tests against moment condition parameter heterogeneity are derived with the relevant Jacobian matrix obtained in terms of the second order own derivatives of the moment indicator in a leading case. GMM and GEL tests of specification based on generalized information matrix equalities appropriate for moment-based models are described and their relation to optimal m-tests against moment condition parameter heterogeneity examined. A fundamental and important difference is noted between GMM and GEL constructions. The paper is concluded by a generalization of these tests to the conditional moment context and the provision of a limited set of simulation experiments to illustrate the efficacy of the proposed tests.  相似文献   

16.

University business incubators (UBIs) are an important part of the ecosystem that supports entrepreneurial activities and economic development. Extant research has focused on examining UBI activities at a single point in time, but there is a paucity of theoretical and empirical work aimed at understanding the forces that explain why and how UBIs change over time. This is an important gap because establishing a university business incubator does not assure its development and growth. We address this issue by drawing upon the Fisher et al. Academy of Management Review, 41(3), 383-409 (2016) Identity-Legitimacy-Life Cycle model to explain how the pursuit of resources and organizational legitimacy shapes the development of UBIs along key strategic and operational dimensions, which has implications for performance evaluation over time. We illustrate with a case study about the creation and evolution of the DMZ, a leading UBI at Ryerson University in Canada. This case provides new insights about the dynamics of UBIs and their relationships with the entrepreneurial ecosystems in which they are embedded. Implications for future research, management practice, and public policy are discussed.

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17.
In this paper, we propose an extension to the first-order branching process with immigration in the presence of fixed covariates and unobservable random effects. The extension permits the possibility that individuals from the second generation of the process may contribute to the total number of offsprings at time \(t\) by producing offsprings of their own. We will study the basic properties of the second order process and discuss a generalized quasilikelihood (GQL) estimation of the mean and variance parameters and the generalized method of moments estimation of the correlation parameters. We will discuss the asymptotic distribution of the GQL estimator by first deriving the influence curve of the estimator. For the fixed effects model we shall derive a forecasting function and the variance of the forecast error. The performance of the proposed estimators and forecasts will be examined through a simulation study.  相似文献   

18.
Individuals living in society are bound together by a social network and, in many social and economic situations, individuals learn by observing the behavior of others in their local environment. This process is called social learning. Learning in incomplete networks, where different individuals have different information, is especially challenging: because of the lack of common knowledge individuals must draw inferences about the actions others have observed, as well as about their private information. This paper reports an experimental investigation of learning in three-person networks and uses the theoretical framework of Gale and Kariv (Games Econ Behav 45:329–346, 2003) to interpret the data generated by the experiments. The family of three-person networks includes several non-trivial architectures, each of which gives rise to its own distinctive learning patterns. To test the usefulness of the theory in interpreting the data, we adapt the Quantal Response Equilibrium (QRE) model of Mckelvey and Palfrey (Games Econ Behav 10:6–38, 1995; Exp Econ 1:9–41, 1998). We find that the theory can account for the behavior observed in the laboratory in a variety of networks and informational settings. This provides important support for the use of QRE to interpret experimental data.  相似文献   

19.
本研究采用实验的方法挖掘广告调节聚焦信息对消费者非欺诈性仿冒奢侈品购买意愿的影响机理。研究结果表明,奢侈品广告信息对消费者仿冒奢侈品购买意愿的影响受消费者自尊水平的调节:对于高自尊的消费者,当广告信息为预防聚焦时,其仿冒奢侈品的购买意愿更低;对于低自尊的消费者,广告调节聚焦信息对其仿冒奢侈品购买意愿的影响不显著。广告信息对消费者仿冒奢侈品购买意愿的影响还受消费者从众倾向的调节:对于低从众倾向的消费者,当广告信息为预防聚焦时,其仿冒奢侈品的购买意愿更低;对于高从众倾向的消费者,广告调节聚焦信息对其仿冒奢侈品购买意愿的影响不显著。  相似文献   

20.
In his protracted dispute with Jan Adam over the early benefits of the Polish shock therapy approach to economic reform, a key, and still intact, component of Jeffrey Sachs' case has been a relatively favourable 1991 opinion poll about Poles' perceptions of the benefits of economic reform. This reported that a substantial majority of Poles felt their standard of living had improved as a result of the first two years of economic reform. This was an apparently powerful argument in favour of Poland's particular shock therapy approach to economic reform, as residents of other East European countries, some subject to more gradualist reforms, responded much less positively to the identical question put as part of the same research programme. However, the cited result should be seen as posing a mystery that is at odds with other monthly polls in Poland and seems incompatible with the results of the 1991 Polish Parliamentary elections, which showed a return of support to post-communist parties. A deeper analysis of opinion polls which follows solves the mystery, when it is shown how the cited result was in error and was published in a form diametrically opposite to the true result.  相似文献   

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