• Title/Summary/Keyword: Likelihood measure

검색결과 184건 처리시간 0.033초

Graphical Methods for Hierarchical Log-Linear Models

  • Hong, Chong-Sun;Lee, Ui-Ki
    • Communications for Statistical Applications and Methods
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    • 제13권3호
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    • pp.755-764
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    • 2006
  • Most graphical methods for categorical data can describe the structure of data and represent a measure of association among categorical variables. Among them the polyhedron plot represents sequential relationships among hierarchical log-linear models for a multidimensional contingency table. This kind of plot could be explored to describe the differences among sequential models. In this paper we suggest graphical methods, containing all the information, that reflect the relationship among all log-linear models in a certain hierarchical structure. We use the ideas of a correlation diagram.

EMG 패턴인식을 이용한 인공팔의 마이크로프로세서 제어 (Microprocessor Control of a Prosthetic Arm by EMG Pattern Recognition)

  • Hong, Suk-Kyo
    • 대한전기학회논문지
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    • 제33권10호
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    • pp.381-386
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    • 1984
  • This paper deals with the microcomputer realization of EMG pattern recognition system which provides identification of motion commands from the EMG signals for the on-line control of a prosthetic arm. A probabilistic model of pattern is formulated in the feature space of integral absolute value(IAV) to describe the relation between a motion command and the location of corresponding pattern. This model enables the derivation of sample density function of a command in the feature space of IAV. Classification is caried out through the multiclass sequential decision process, where the decision rule and the stopping rule of the process are designed by using the simple mathematical formulas defined as the likelihood probability and the decision measure, respectively. Some floating point algorithms such as addition, multiplication, division, square root and exponential function are developed for calculating the probability density functions and the decision measure. Only six primitive motions and one no motion are incorporated in this paper.

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주제공원 이용자 만족의 결정인자에 관한 연구 - 에버랜드를 중심으로 - (The Determinants of Theme Park Users' Satisfaction; Everland)

    • 한국조경학회지
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    • 제26권3호
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    • pp.189-198
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    • 1998
  • This study explored the effects of expectatioin, performance, and disconfirmatoni on satisfaction of theme park users. Everland was chosen as the study area, and 260 users were selected by the nonprobability sampling. In expectation disconfirmation paradigm, expectation should be measured before purchase, and performance, disconfirmation and satisfaction should be measured after purchase. An entrance survey was done to measure expectation, and an exit survey to measure performance, disconfirmation, and satisfaction. Maximum likelihood method was used to estimate structural equation model by the LISREL 7.2. Performance had the most significant effect on satisfaction among three variables. The satisfaction of theme park users depends largely on it, therefore, the consideration of visitors' performance should e essential for managers.

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BMS 알고리즘을 이용한 거절기능 성능 향상 (Improvement of Confidence Measure Performance using Background Model Set Algorithm)

  • 김병돈;이경록;김진영;최승호
    • 대한음성학회:학술대회논문집
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    • 대한음성학회 2003년도 5월 학술대회지
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    • pp.79-82
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    • 2003
  • In this paper, we proposed Backgorund Model Set algorithm for the speaker verification to improve the shortcoming of calculating process in conventional confidence measure(CM). CM is to display relative likelihood between recognized models and unrecognized models. Unrecognized models is known as antiphone models. Calculate probability and standard deviation using all phonemes at process that compose antiphone model. At this process, antiphone CM brought bad result. Also, recognition time increases. In order problem, we studied about method to reconstitute average and standard deviation taking BMS algorithm using antiphoneme that near phoneme of CM calculation.

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Collapse fragility analysis of the soil nail walls with shotcrete concrete layers

  • Bayat, Mahmoud;Emadi, Amin;Kosariyeh, Amir Homayoun;Kia, Mehdi;Bayat, Mahdi
    • Computers and Concrete
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    • 제29권 5호
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    • pp.279-283
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    • 2022
  • The seismic analytic collapse fragility of soil nail wall structures with a shotcrete concrete covering is investigated in this paper. The finite element modeling process has been well described. The fragility function evaluates the link between ground motion intensities and the likelihood of reaching a specific level of damage. The soil nail wall has been subjected to incremental dynamic analysis (IDA) from medium to strong ground vibrations. The nonlinear dynamic analysis of the soil nail wall uses a set of 20 earthquake ground motions with varying PGAs. PGD is utilized as an intensity measure, the numerical findings demonstrate that the soil nailing wall reaction is particularly sensitive to earthquake intensity measure (IM).

다학제간 지식융합을 위한 '융합동기' 척도 개발 연구 (Development of the 'convergence motive' scale for interdisciplinary knowledge fusion)

  • 박성미;양황규
    • 수산해양교육연구
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    • 제27권6호
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    • pp.1880-1890
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    • 2015
  • The purpose of this study was to development of the 'convergence motive' scale for interdisciplinary knowledge fusion. Based on results from literature review, this study clarifies a theoretical ground for 'convergence motive'. Initial items to measure this concept were verified by content analysis and then finalized. After a pilot test done with 568 college students, gathered data were analyzed by item selection and exploratory factor analysis to verify their validity. Next, the main test implemented with 1,211 college students was analyzed with exploratory factor analysis using the method for rotation based on maximum likelihood analysis and direct oblimin for validating the final items to measure 'convergence motive'. As a result, the scale for 'convergence motive' consists of 43 items to measure the following four factors: collaboration to identifying and solving problems, challenge of a new perspective, communication for convergence, cohesion for convergence. Construct validity and criterion-related validity were performed at last to check this scale's theoretical construct. In conclusion, this study concluded that the scales for convergence motive could be generalized and applicable to other samples.

Learning Similarity with Probabilistic Latent Semantic Analysis for Image Retrieval

  • Li, Xiong;Lv, Qi;Huang, Wenting
    • KSII Transactions on Internet and Information Systems (TIIS)
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    • 제9권4호
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    • pp.1424-1440
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    • 2015
  • It is a challenging problem to search the intended images from a large number of candidates. Content based image retrieval (CBIR) is the most promising way to tackle this problem, where the most important topic is to measure the similarity of images so as to cover the variance of shape, color, pose, illumination etc. While previous works made significant progresses, their adaption ability to dataset is not fully explored. In this paper, we propose a similarity learning method on the basis of probabilistic generative model, i.e., probabilistic latent semantic analysis (PLSA). It first derives Fisher kernel, a function over the parameters and variables, based on PLSA. Then, the parameters are determined through simultaneously maximizing the log likelihood function of PLSA and the retrieval performance over the training dataset. The main advantages of this work are twofold: (1) deriving similarity measure based on PLSA which fully exploits the data distribution and Bayes inference; (2) learning model parameters by maximizing the fitting of model to data and the retrieval performance simultaneously. The proposed method (PLSA-FK) is empirically evaluated over three datasets, and the results exhibit promising performance.

한국어 퍼지 언어변수를 이용한 리스크 평가의 논리적 일관성 (Logical Consistency in Risk Assessment using the Korean Fuzzy Linguistic Variables)

  • 임현교;변상훈
    • 한국안전학회지
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    • 제31권4호
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    • pp.120-125
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    • 2016
  • Usually, a risk can be expressed as a product of likelihood and consequence of a hazard factor. Therefore, conventional risk assessment is carried out by frequency analysis and severity analysis, in turns. However, it is well known that intuitive thinking is another excellent way of thinking of human beings. This study aimed to confirm whether there exist any difference in risk assessment results derived by two different procedures - intuitive and analytical. Thus, the present study showed 10 different illustrations to 30 undergraduate students. Their responses were organized as fuzzy membership functions, and summarized as risk assessments, and compared. The results were also verified with the help of statistical hypothesis testing, which showed no significant difference. On the contrary, however, similarity measure used in fuzzy set theory was not credible as anticipated. Many cases failed to satisfy statistical hypothesis even with similarity measure higher than 0.60 so that only a trend could be accepted. In addition, a subject showed a somewhat consistent logical discrepancy in his response, which implied the necessity of sincere analysis in fuzzy formulations.

Evaluation of Multi-criteria Performances of the TOPMODEL Simulations in a Small Forest Catchment based on the Concept of Equifinality of the Multiple Parameter Sets

  • Choi, Hyung Tae;Kim, Kyongha;Jun, Jae-Hong;Yoo, Jae-Yun;Jeong, Yong-Ho
    • 한국산림과학회지
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    • 제95권5호
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    • pp.569-579
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    • 2006
  • This study focuses on the application of multi-criteria performance measures based on the concept of equifinality to the calibration of the rainfall-runoff model TOPMODEL in a small deciduous forest catchment. The performance of each parameter set was evaluated by six performance measures, individually, and each set was identified as a behavioral or non-behavioral parameter set by a given behavioral acceptance threshold. Many behavioral parameter sets were scattered throughout the parameter space, and the range of model behavior and the sensitivity for each parameter varied considerably between the different performance measures. Sensitivity was very high in some parameters, and varied depending on the kind of performance measure as well. Compatibilities of behavioral parameter sets between different performance measures also varied, and very few parameter sets were selected to be used in making god predictions for all performance measures. Since different behavioral parameter sets with different likelihood weights were obtained for each performance measure, the decision on which performance measure to be used may be very important to achieve the goal of study. Therefore, one or more suitable performance measures should be selected depending on the environment and the goal of a study, and this may lead to decrease model uncertainty.

Construction of bivariate asymmetric copulas

  • Mukherjee, Saikat;Lee, Youngsaeng;Kim, Jong-Min;Jang, Jun;Park, Jeong-Soo
    • Communications for Statistical Applications and Methods
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    • 제25권2호
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    • pp.217-234
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    • 2018
  • Copulas are a tool for constructing multivariate distributions and formalizing the dependence structure between random variables. From copula literature review, there are a few asymmetric copulas available so far while data collected from the real world often exhibit asymmetric nature. This necessitates developing asymmetric copulas. In this study, we discuss a method to construct a new class of bivariate asymmetric copulas based on products of symmetric (sometimes asymmetric) copulas with powered arguments in order to determine if the proposed construction can offer an added value for modeling asymmetric bivariate data. With these newly constructed copulas, we investigate dependence properties and measure of association between random variables. In addition, the test of symmetry of data and the estimation of hyper-parameters by the maximum likelihood method are discussed. With two real example such as car rental data and economic indicators data, we perform the goodness-of-fit test of our proposed asymmetric copulas. For these data, some of the proposed models turned out to be successful whereas the existing copulas were mostly unsuccessful. The method of presented here can be useful in fields such as finance, climate and social science.