• 제목/요약/키워드: Under-representation

검색결과 395건 처리시간 0.024초

A New Integral Representation of the Coverage Probability of a Random Convex Hull

  • Son, Won;Ng, Chi Tim;Lim, Johan
    • Communications for Statistical Applications and Methods
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    • 제22권1호
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    • pp.69-80
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    • 2015
  • In this paper, the probability that a given point is covered by a random convex hull generated by independent and identically-distributed random points in a plane is studied. It is shown that such probability can be expressed in terms of an integral that can be approximated numerically by function-evaluations over the grid-points in a 2-dimensional space. The new integral representation allows such probability be computed efficiently. The computational burdens under the proposed integral representation and those in the existing literature are compared. The proposed method is illustrated through numerical examples where the random points are drawn from (i) uniform distribution over a square and (ii) bivariate normal distribution over the two-dimensional Euclidean space. The applications of the proposed method in statistics are are discussed.

클러스터 분석을 위한 IRC기반 클러스터 개수 자동 결정 방법 (Systematic Determination of Number of Clusters Based on Input Representation Coverage)

  • 신미영
    • 전자공학회논문지CI
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    • 제41권6호
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    • pp.39-46
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    • 2004
  • 클러스터 분석에 있어 중요한 문제 중의 하나는 주어진 데이터에 내재된 적절한 클러스터의 수를 찾아내는 것이다. 본 논문에서는 이러한 클러스터의 개수를 체계적으로 결정하기 위하여 IRC (Input Representation Coverage) 개념을 새로이 정의하고, 이를 이용하여 주어진 데이터에 적합한 클러스터의 개수를 자동 결정하는 방법을 제시한다. 또한, 이러한 방법의 유용성 및 응용성을 알아보기 위하여 가상 데이터를 가지고 분석 실험을 하였으며, 실험을 통해 데이터에 내재된 실제 클러스터의 개수를 찾아내는 데에 제안된 방법이 매우 유용하게 사용될 수 있음을 보여준다.

Multiscale Spatial Position Coding under Locality Constraint for Action Recognition

  • Yang, Jiang-feng;Ma, Zheng;Xie, Mei
    • Journal of Electrical Engineering and Technology
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    • 제10권4호
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    • pp.1851-1863
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    • 2015
  • – In the paper, to handle the problem of traditional bag-of-features model ignoring the spatial relationship of local features in human action recognition, we proposed a Multiscale Spatial Position Coding under Locality Constraint method. Specifically, to describe this spatial relationship, we proposed a mixed feature combining motion feature and multi-spatial-scale configuration. To utilize temporal information between features, sub spatial-temporal-volumes are built. Next, the pooled features of sub-STVs are obtained via max-pooling method. In classification stage, the Locality-Constrained Group Sparse Representation is adopted to utilize the intrinsic group information of the sub-STV features. The experimental results on the KTH, Weizmann, and UCF sports datasets show that our action recognition system outperforms the classical local ST feature-based recognition systems published recently.

A design of discrete-time integral controllers under skewed sampling

  • Ishihara, Tadashi;Guo, Hai-Jiao;Taketa-Hiroshi
    • 제어로봇시스템학회:학술대회논문집
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    • 제어로봇시스템학회 1993년도 한국자동제어학술회의논문집(국제학술편); Seoul National University, Seoul; 20-22 Oct. 1993
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    • pp.428-433
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    • 1993
  • First, we propose a transparent and efficient design of discrete-time integral controllers accounting sampling skew. Based on the proposed controller, we derive a state-space representation of doubly coprime factorization including integral action. The representation is then used to obtain a convenient state-space parametrization of discrete-time two-degree-of-freedom integral controllers acconting sampling skew.

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Hypercube 영역의 집합으로 표현된 패턴인식 알고리즘의 설계 (A Design of Pattern Recognition Algorithm as a Collection of Hypercubic Regions)

  • Baek Sop Kim
    • 전자공학회논문지B
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    • 제29B권7호
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    • pp.23-29
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    • 1992
  • In this paper, a method of representing the pattern classifier as a collection of hypercubic regions is proposed. This representation has following advantages over the conventional ones : 1) a simple form of human knowledge can be used in designing the classifier, 2) the form of the classifier is suit for the rule-based system, and 3) this can reduce the classification time. A method of synthesis of the classifier under this representation is also proposed and the experimental result shows that the proposed method is faster than the well-known nearest neighbor classifier.

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Strong Representations for LAD Estimators in AR(1) Models

  • Kang, Hee-Jeong;Shin, Key-Il
    • Journal of the Korean Statistical Society
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    • 제27권3호
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    • pp.349-358
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    • 1998
  • Consider the AR(1) model $X_{t}$=$\beta$ $X_{t-1}$+$\varepsilon$$_{t}$ where $\beta$ < 1 is an unknown parameter to be estimated and {$\varepsilon$$_{t}$} denotes the independent and identically distributed error terms with unknown common distribution function F. In this paper, a strong representation for the least absolute deviation (LAD) estimate of $\beta$ in AR(1) models is obtained under some mild conditions on F. on F.F.

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THE SET OF PRIORS IN THE REPRESENTATION OF CHOQUET EXPECTATION WHEN A CAPACITY IS SUBMODULAR

  • KIM, JU HONG
    • 한국수학교육학회지시리즈B:순수및응용수학
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    • 제22권4호
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    • pp.333-342
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    • 2015
  • We show that the set of priors in the representation of Choquet expectation is the one of equivalent martingale measures under some conditions, when given capacity is submodular. It is proven via Peng’s g-expectation and related topics.

Solving Robust EOQ Model Using Genetic Algorithm

  • Lim, Sung-Mook
    • Management Science and Financial Engineering
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    • 제13권1호
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    • pp.35-53
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    • 2007
  • We consider a(worst-case) robust optimization version of the Economic Order Quantity(EOQ) model. Order setup costs and inventory carrying costs are assumed to have uncertainty in their values, and the uncertainty description of the two parameters is supposed to be given by an ellipsoidal representation. A genetic algorithm combined with Monte Carlo simulation is proposed to approximate the ellipsoidal representation. The objective function of the model under ellipsoidal uncertainty description is derived, and the resulting problem is solved by another genetic algorithm. Computational test results are presented to show the performance of the proposed method.

Simple Estimation in Proportional Odds Model under Censoring

  • Kim, Ju-Sung;Seo, Min-Ja;Won, Dong-Yu
    • Journal of the Korean Data and Information Science Society
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    • 제16권4호
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    • pp.889-898
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    • 2005
  • In this paper we propose a new estimator of relative odds ratio in the two-sample case of proportional odds model under censorship. Also, we show that the estimator consistent and asymptotically normal by using martingale-representation. The efficiency of the proposed is assessed through a simulation study.

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웨이브릿 고장률 함수를 갖는 최소수리 교체모형 개발 (Development of Replacement Models under Minimal Repair with Wavelet Failure Rate Functions)

  • 최성운
    • 대한안전경영과학회지
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    • 제3권4호
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    • pp.91-101
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    • 2001
  • This paper is to develop replacement models under minimal repair with exponential polynomial wavelet failure rate function. Wavelets have good time-frequency localization, fast algorithms and parsimonious representation. Also this study is presented along with numerical examples using sensitivity analysis for exponential polynomial trigonometric failure rate function.

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