• 제목/요약/키워드: model symmetry

검색결과 237건 처리시간 0.019초

GAUSS DISCREPANCY TYPE MEASURE OF DEGREE OF RESIDUALS FROM SYMMETRY FOR SQUARE CONTINGENCY TABLES

  • Tomizawa, Sadao;Murata, Mariko
    • Journal of the Korean Statistical Society
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    • 제21권1호
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    • pp.59-69
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    • 1992
  • A measure is proposed to represent the degree of residuals from the symmetry model for square contingency tables with nominal categories. The measure is derivedby modifying the sum of squared singular values for a skew symmetric matrix of the residuals from the symmetry model. The proposed measure would be useful for comparing the degree of residuals from the symmetry model in several tables.

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3차원 대칭단면 유동장에서의 개선된 난류모델 (Improved Turbulence Model on the 3 Dimensional Plane of Symmetry Flow)

  • 손창현
    • 한국전산유체공학회지
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    • 제2권2호
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    • pp.1-8
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    • 1997
  • Two versions of anisotropic k-ε turbulence model are incorporated in the modified k-ε model of Sohn et al. to avoid the need for the experimental normal stress value in the model and applied to convergent and divergent flows with strong and adverse pressure gradients in the plane of symmetry of a body of revolution. The models are the nonlinear k-ε model of Speziale and the anisotropic model of Nisizima & Yoshizawa. All of the models yield satisfactory results for relatively complex flow on a plane-of-symmetry boundary layer. The results of the models are compared with those results of experimental normal stress value.

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THE RELATIONSHIP BETWEEN NONCOMMUTATIVE AND LORENTZVIOLATING PARAMETERS IN QUANTUM

  • HEIDARI, A.;GHORBANI, F.;GHORBANI, M.
    • Journal of the Korean Society for Industrial and Applied Mathematics
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    • 제16권3호
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    • pp.205-216
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    • 2012
  • When it comes to Lorentz symmetry violation, there are generally two approaches to studying noncommutative field theory: 1) conventional fields are equivalent to noncommutative fields; however, symmetry groups are larger. 2) The symmetry group is the same as conventional standard model's symmetry group; but fields here are written based on the Seiberg-Witten map. Here by adopting the first approach, we aim to connect Lorentz violation coefficients with noncommutative parameters and compare the results with the second approach's results. Through the experimental values obtained for the Lorentz-violating parameters, we obtain a limit of noncommutative symmetry.

Neutrino Oscillation and S4 Flavor Symmetry

  • Park, Jong-Chul
    • Applied Science and Convergence Technology
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    • 제27권5호
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    • pp.86-89
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    • 2018
  • Observations of neutrino oscillations are very strong evidence for the existence of neutrino masses and mixing. From recent experimental results on neutrino oscillation, we find that neutrino mixing angles are quite consistent with the so-called tri-bi-maximal mixing pattern, but the deviation from observational results is non-negligible. However, the tri-bi-maximal mixing pattern is still useful as a leading order approximation and provides a good guideline to search for the flavor symmetry in the neutrino sector. We introduce the $S_4$ permutation symmetry as a flavor symmetry to the standard model of particle physics with additional particle contents of heavy right-handed neutrinos and scalar fields. Finally, we obtain the tri-bi-maximal mixing pattern as a mixing matrix in the lepton sector within the suggested model. To derive the required unitary mixing matrix for the neutrino sector, the double seesaw mechanism is utilized.

Visualizations for Matched Pairs Models Using Modified Correspondence Analysis

  • Lee, Chanyoon;Choi, Yong-Seok
    • Communications for Statistical Applications and Methods
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    • 제21권4호
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    • pp.275-284
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    • 2014
  • Matched pairs are twice continuously measured data with the same categories. They can be represented as the square contingency tables. We can also consider symmetry and marginal homogeneity. Moreover, we can infer the matched pairs models; the symmetry model, the quasi-symmetry model, and the ordinal quasi-symmetry model. These inferences are involved in assumptions for special distributions. In this study, we visualize matched pairs models using modified correspondence analysis. Modified correspondence analysis can be used when square contingency tables are given; consequently, it is involved in the square and asymmetric correspondence matrix. This technique does not need assumptions for special distributions and is more helpful than the correspondence analysis to visualize matched pairs models.

MEASURE OF DEPARTURE FROM QUASI-SYMMETRY AND BRADLEY-TERRY MODELS FOR SQUARE CONTINGENCY TABLES WITH NOMINAL CATEGORIES

  • Kouji Tahata;Nobuko Miyamoto;Sadao Tomizawa
    • Journal of the Korean Statistical Society
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    • 제33권1호
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    • pp.129-147
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    • 2004
  • For square contingency tables with nominal categories, this paper proposes a measure to represent the degree of departure from the quasi-symmetry (QS) model and the Bradley-Terry (BT) model. The measure proposed is expressed by using the Cressie and Read (1984)'s power-divergence or Patil and Taillie (1982)'s diversity index. The measure lies between 0 and 1, and it is useful for comparing the degree of departure from QS or BT in several tables.

로그선형모형을 이용한 복수 평가자들간의 신뢰도에 관한 연구 (Reliability for Multiple Reviewers by using Loglinear Models)

  • 박병주;이성임;이영조;김동현;권호장;배종면;신명희;하미나;한상환
    • Journal of Preventive Medicine and Public Health
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    • 제30권4호
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    • pp.719-728
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    • 1997
  • To guarantee the inter-reviewer reliability is very important in evaluating the quality of large number of clinical research papers by multiple reviewers. We cannot find reports on statistical methods for evaluating reliability for multiple raters in clinical research field. The purpose of this paper is to introduce the statistical methods focused on kappa statistic and five kinds of loglinear models for, which can be applied when evaluating the reliability of multiple raters. We have applied these methods to the result of a project, in which seven reviewers have evaluated the quality of 33 papers with regard to four aspects of paper contents including study hypothesis, study design, study population, study method, data analysis and interpretation. Among the five loglinear models including Symmetry model, Conditional symmetry model, Quasi-symmetry model, Independence model, and Quasi-independence model, Quasi-symmetry model shows the best model of fitting. And the level of reliability among seven reviewers revealed to be acceptable as meaningful.

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