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Faddeev null-plane model of the nucleon
Physical Review C, 1995The nucleon is formulated as a relativistic system of three constituent quarks interacting via a zero-range two-body force in the null plane. The covariance of the null-plane Faddeev-like equation under kinematical front-form boosts is discussed. The nucleon wave function is obtained from the numerical solution of the Faddeev equation in the null plane.
, de Araújo WR +2 more
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P Values for Composite Null Models
Journal of the American Statistical Association, 2000Abstract The problem of investigating compatibility of an assumed model with the data is investigated in the situation when the assumed model has unknown parameters. The most frequently used measures of compatibility are p values, based on statistics T for which large values are deemed to indicate incompatibility of the data and the model.
M. J. Bayarri, James O. Berger
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1994
Abstract The problem with models in phylogenetic inference is one of regress or circularity. Sound models demand either some knowledge of phylogeny, or assumptions about it. If knowledge is claimed, how was that knowledge gained? If assumptions are held to be merely provisional or approximate, how will they be tested by phylogenies that ...
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Abstract The problem with models in phylogenetic inference is one of regress or circularity. Sound models demand either some knowledge of phylogeny, or assumptions about it. If knowledge is claimed, how was that knowledge gained? If assumptions are held to be merely provisional or approximate, how will they be tested by phylogenies that ...
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Toward ecologically explicit null models of nestedness
Oecologia, 2007A community is "nested" when species assemblages in less rich sites form nonrandom subsets of those at richer sites. Conventional null models used to test for statistically nonrandom nestedness are under- or over-restrictive because they do not sufficiently isolate ecological processes of interest, which hinders ecological inference. We propose a class
Jeffrey E, Moore, Robert K, Swihart
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Null Hypothesis Models in Legislative Studies
The Journal of Politics, 1983P olitical scientists often refer to the existence of "coalitions" in Congress, but remarkably little effort has been made to discover the reasons why the votes of various congressmen might be similar. It may be that coalition formation-the explicit coordination of voting decisions-has indeed occurred.
Thomas H. Hammond, Jane M. Fraser
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SWAP ALGORITHMS IN NULL MODEL ANALYSIS
Ecology, 2003Null model analysis is an important research tool in community ecology (Gotelli 2001). Researchers compare community data with randomized data to ask how communities would appear if they were structured only by stochastic factors (Gotelli and Graves 1996).
Nicholas J. Gotelli, Gary L. Entsminger
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2016
In the last chapter, a qualitative comparison of various real-world structures with classic random graph models revealed that complex networks are non-random in many aspects. This chapter focuses on the question of how to quantify the statistical significance of an observed network structure with respect to a given random graph model.
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In the last chapter, a qualitative comparison of various real-world structures with classic random graph models revealed that complex networks are non-random in many aspects. This chapter focuses on the question of how to quantify the statistical significance of an observed network structure with respect to a given random graph model.
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Null Models in Cluster Validation
1996A brief overview is given of the problem of validation in classification studies. Attention is concentrated on the specification of appropriate null models for data, with respect to which one may assess some cluster structure that has been obtained as the output of a clustering algorithm.
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Research frontiers in null model analysis
Global Ecology and Biogeography, 2001AbstractNull models are pattern‐generating models that deliberately exclude a mechanism of interest, and allow for randomization tests of ecological and biogeographic data. Although they have had a controversial history, null models are widely used as statistical tools by ecologists and biogeographers.
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