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1.
Recent algebraic parametric estimation techniques (see Fliess and Sira-Ramírez, ESAIM Control Optim Calc Variat 9:151–168,
2003, 2008) led to point-wise derivative estimates by using only the iterated integral of a noisy observation signal (see Mboup et al.
2007, Numer Algorithms 50(4):439–467, 2009). In this paper, we extend such differentiation methods by providing a larger choice of parameters in these integrals: they
can be reals. For this, the extension is done via a truncated Jacobi orthogonal series expansion. Then, the noise error contribution
of these derivative estimations is investigated: after proving the existence of such integral with a stochastic process noise,
their statistical properties (mean value, variance and covariance) are analyzed. In particular, the following important results
are obtained:
(a) |
the bias error term, due to the truncation, can be reduced by tuning the parameters, 相似文献
2.
Hagit Benbaji 《Acta Analytica》2008,23(1):55-67
Two-dimensional semantics aims to eliminate the puzzle of necessary a posteriori and contingent a priori truths. Recently
many argue that even assuming two-dimensional semantics we are left with the puzzle of necessary and a posteriori propositions.
Stephen Yablo (Pacific Philosophical Quarterly, 81, 98–122, 2000) and Penelope Mackie (Analysis, 62(3), 225–236, 2002) argue that a plausible sense of “knowing which” lets us know the object of such a proposition, and yet its necessity is
“hidden” and thus a posteriori. This paper answers this objection; I argue that given two-dimensional semantics you cannot
know a necessary proposition without knowing that it is true.
3.
Simon Rodan 《Computational & Mathematical Organization Theory》2008,14(3):222-247
Earlier theoretical accounts of collective learning relied on rules and operating procedures as the organizational memory
(March in Organ. Sci. 2(1):71–87, 1991; Rodan in Scand. J. Manag. 21:407–428, 2005). This paper builds on this tradition drawing on ideas from social network theory. Learning is modeled as a social-psychological
process (Darr and Kurtzberg in Organ. Behav. Hum. Decis. Process. 82(1):28–44, 2000; Rulke et al. in Organ. Behav. Hum. Decis. Process. 82(1):134–149, 2000), in which organizations learn by exchanging information internally between their members (Argote et al. in Organ. Behav.
Hum. Decis. Process. 82(1):1–8, 2000; Carley in Am. Soc. Rev. 56(3):331–354, 1991; Carley in Soc. Perspect. 48(4):547–571, 1995). Learning is also characterized as stochastic and creative (Gruenfeld et al. in Organ. Behav. Hum. Decis. Process. 82(1):45–59,
2000). This model is used to explore predictions about the effect social networks have on idea generation and learning and alternative
strategies for choosing from whom to seek information.
4.
Jeffrey B. Vancouver Charles A. Scherbaum 《Computational & Mathematical Organization Theory》2008,14(1):1-22
Self-regulation theories in applied psychology disagree about whether action or perceptions are the focus of regulation. Computational
models based on the two conceptualizations were constructed and simulated. In one scenario, they performed identically and
in conjunction with participants in a study of the goal-level effect (Vancouver et al., Organ Res Methods 8:100–127, 2005). In another scenario they created differentiating predictions and only the computational model based on the self-regulation
of perceptions matched the data of participants. Implications for research and practice are discussed.
5.
Pratim Sengupta Uri Wilensky 《International Journal of Computers for Mathematical Learning》2009,14(1):21-50
Electricity is regarded as one of the most challenging topics for students of all ages. Several researchers have suggested
that na?ve misconceptions about electricity stem from a deep incommensurability (Slotta and Chi 2006; Chi 2005) or incompatibility (Chi et al.
1994) between na?ve and expert knowledge structures. In this paper we argue that adopting an emergent levels-based perspective
as proposed by Wilensky and Resnick (1999), allows us to reconceive commonly noted misconceptions in electricity as behavioral evidences of “slippage between levels,”
i.e., these misconceptions appear when otherwise productive knowledge elements are sometimes activated inappropriately due
to certain macro-level phenomenological cues only. We then introduce NIELS (NetLogo Investigations In Electromagnetism), a
curriculum of emergent multi-agent-based computational models. NIELS models represent phenomena such as electric current and
resistance as emergent from simple, body-syntonic interactions between electrons and other charges in a circuit. We discuss results from a pilot
implementation of NIELS in an undergraduate physics course, that highlight the ability of an emergent levels-based approach
to provide students with a deep, expert-like understanding of the relevant phenomena by bootstrapping, rather than discarding their existing repertoire of intuitive knowledge.
6.
Jana Diesner Kathleen M. Carley 《Computational & Mathematical Organization Theory》2008,14(3):248-262
Previous research suggests that one field with a strong yet unsatisfied need for automatically extracting instances of various
entity classes from texts is the analysis of socio-technical systems (Feldstein in Media in Transition MiT5, 2007; Hampe et al. in Netzwerkanalyse und Netzwerktheorie, 2007; Weil et al. in Proceedings of the 2006 Command and Control Research and Technology Symposium, 2006; Diesner and Carley in XXV Sunbelt Social Network Conference, 2005). Traditional as well as non-traditional and customized sets of entity classes and the relationships between them are often
specified in ontologies or taxonomies. We present a Conditional Random Fields (CRF)-based approach to distilling a set of
entities that are defined in an ontology originating from organization science. CRF, a supervised sequential machine learning
technique, facilitates the derivation of relational data from corpora by locating and classifying instances of various entity
classes. The classified entities can be used as nodes for the construction of socio-technical networks. We find the outcome
sufficiently accurate (82.7 percent accuracy of locating and classifying entities) for future application in the described problem domain. We propose using the presented methodology
as a crucial step in the process of advanced modeling and analysis of complex and dynamic networks.
7.
Dor Abrahamson Uri Wilensky 《International Journal of Computers for Mathematical Learning》2007,12(1):23-55
We introduce a design-based research framework, learning axes and bridging tools, and demonstrate its application in the preparation and study of an implementation of a middle-school experimental computer-based
unit on probability and statistics, ProbLab (Probability Laboratory, Abrahamson and Wilensky 2002 [Abrahamson, D., & Wilensky, U. (2002). ProbLab. Northwestern University, Evanston, IL: The Center for Connected Learning and Computer-Based Modeling, Northwestern University.
]). ProbLab is a mixed-media unit, which utilizes traditional tools as well as the NetLogo agent-based modeling-and-simulation environment (Wilensky 1999) [Wilensky, U. (1999). NetLogo. Northwestern University, Evanston, IL: The Center for Connected Learning and Computer-Based Modeling ] and HubNet, its technological extension for facilitating participatory simulation activities in networked classrooms (Wilensky and Stroup
1999a) [Wilensky, U., & Stroup, W. (1999a). HubNet. Evanston, IL: The Center for Connected Learning and Computer-Based Modeling, Northwestern University]. We will focus on
the statistics module of the unit, Statistics As Multi-Participant Learning-Environment Resource (S.A.M.P.L.E.R.). The framework shapes the design rationale toward creating and developing learning tools, activities, and facilitation guidelines.
The framework then constitutes a data-analysis lens on implementation cases of student insight into the mathematical content.
Working with this methodology, a designer begins by focusing on mathematical representations associated with a target concept—the
designer problematizes and deconstructs each representation into a pair of historical/cognitive antecedents (idea elements),
each lying at the poles of a learning axis. Next, the designer creates bridging tools, ambiguous artifacts bearing interaction properties of each of the idea elements, and develops activities with these learning
tools that evoke cognitive conflict along the axis. Students reconcile the conflict by means of articulating strategies that
embrace both idea elements, thus integrating them into the target concept.
The research reported on this paper was funded by NSF ROLE Grant No. REC-0126227. The opinions expressed here are those of
the authors and do not necessarily reflect those of NSF. This paper is based on the authors’ AERA 2004 paper titled S.A.M.P.L.E.R.: Statistics As Multi-Participant Learning-Environment Resource.
8.
Laurent Bartholdi 《Israel Journal of Mathematics》2006,154(1):93-139
We develop the theory of “branch algebras”, which are infinite-dimensional associative algebras that are isomorphic, up to
taking subrings of finite codimension, to a matrix ring over themselves. The main examples come from groups acting on trees.
In particular, for every field
% MathType!End!2!1! we contruct a
% MathType!End!2!1! which
9.
In this paper we establish results on the existence of nontangential limits for weighted
-harmonic functions in the weighted Sobolev space
, for some q>1 and w in the Muckenhoupt A
q
class, where
is the unit ball in
. These results generalize the ones in Sect. 3 of Koskela et al., Trans. Am. Math. Soc. 348(2), 755–766, 1996, where the weight was identically equal to one. Weighted
-harmonic functions are weak solutions of the partial differential equation
10.
Choonkil Park 《Acta Appl Math》2008,102(1):71-85
This paper is a survey on the Hyers–Ulam–Rassias stability of the following Cauchy–Jensen functional equation in C
*-algebras:
11.
T. E. Armstrong 《International Journal of Game Theory》1991,20(1):65-90
We consider games in coalition function form on a, generally infinite, algebra of coalitions. For finite algebras the additive part mappingv E(v ¦) is the usual. The concern here is the analogue for infinite algebras. The useful construction is the finitely additive stochastic process of additive parts of the game on the filtration
f
of finite subalgebras of.It is shown that
is an isomorphism between:
12.
P. Moszkowski 《Periodica Mathematica Hungarica》1989,20(2):147-154
The major sequences of lengthn are defined as the words withn letters taken from the integers 1, 2, ,n and containing at least
13.
Marcel Erné 《Algebra Universalis》1993,30(4):538-580
We study several kinds of distributivity for concept lattices of contexts. In particular, we find necessary and sufficient conditions for a concept lattice to be
14.
We construct a self-avoiding process taking values in the finite Sierpinski gasket, and study its properties. We then study continuum limit processes that are suggested by the statistical mechanics of self-avoiding paths on the pre-Sierpinski gasket. We prove that there are three types of continuum limit processes according to the parameters defining the statistical mechanics of self-avoiding paths:
15.
Let (G, τ) be a commutative Hausdorff locally solid lattice group. In this paper we prove the following:
16.
Abstract This paper develops the model theory of ordered structures that satisfy Keisler’s regularity scheme and its strengthening REF
(the reflection scheme) which is an analogue of the reflection principle of Zermelo-Fraenkel set theory. Here is a language with a distinguished linear order <, and REF
consists of formulas of the form
17.
In this paper, we show that algebraic extensions of semi-hyponormal operators (defined below) are subscalar. As corollaries we get the following:
18.
Two partial ordersP andQ on a setX arecomplementary (written asPQ) if they share no ordered pairs (except for loops) but the transitive closure of the union is all possible ordered pairs. For each positive integern we form a graph Pos
n
consisting of all nonempty partial orders on {1, ,n} with edges denoting complementation. We investigate here properties of the graphs Pos
n
. In particular, we show:
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