• Title/Summary/Keyword: estimation of probability density function

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Verification and estimation of a posterior probability and probability density function using vector quantization and neural network (신경회로망과 벡터양자화에 의한 사후확률과 확률 밀도함수 추정 및 검증)

  • 고희석;김현덕;이광석
    • The Transactions of the Korean Institute of Electrical Engineers
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    • v.45 no.2
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    • pp.325-328
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    • 1996
  • In this paper, we proposed an estimation method of a posterior probability and PDF(Probability density function) using a feed forward neural network and code books of VQ(vector quantization). In this study, We estimates a posterior probability and probability density function, which compose a new parameter with well-known Mel cepstrum and verificate the performance for the five vowels taking from syllables by NN(neural network) and PNN(probabilistic neural network). In case of new parameter, showed the best result by probabilistic neural network and recognition rates are average 83.02%.

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Non-parametric Density Estimation with Application to Face Tracking on Mobile Robot

  • Feng, Xiongfeng;Kubik, K.Bogunia
    • 제어로봇시스템학회:학술대회논문집
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    • 2001.10a
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    • pp.49.1-49
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    • 2001
  • The skin color model is a very important concept in face detection, face recognition and face tracking. Usually, this model is obtained by estimating a probability density function of skin color distribution. In many cases, it is assumed that the underlying density function follows a Gaussian distribution. In this paper, a new method for non-parametric estimation of the probability density function, by using feed-forward neural network, is used to estimate the underlying skin color model. By using this method, the resulting skin color model is better than the Gaussian estimation and substantially approaches the real distribution. Applications to face detection and face ...

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A Study on the Recursive Parameter Estimation Density Function Algorithm of the Probability (확률밀도합수의 축차모수추정방식에 관한 연구)

  • 한영렬;박진수
    • The Journal of Korean Institute of Communications and Information Sciences
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    • v.9 no.4
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    • pp.163-169
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    • 1984
  • We propose a new parameter estimation algorithm that converges with probability one and in mean square, if the mean is the function of parameter of the probability density function. This recursive algorithm is applicable also even though the parameters we estimate are multiparameter case. And the results are shown by the computer simulation.

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Identification of the associations between genes and quantitative traits using entropy-based kernel density estimation

  • Yee, Jaeyong;Park, Taesung;Park, Mira
    • Genomics & Informatics
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    • v.20 no.2
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    • pp.17.1-17.11
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    • 2022
  • Genetic associations have been quantified using a number of statistical measures. Entropy-based mutual information may be one of the more direct ways of estimating the association, in the sense that it does not depend on the parametrization. For this purpose, both the entropy and conditional entropy of the phenotype distribution should be obtained. Quantitative traits, however, do not usually allow an exact evaluation of entropy. The estimation of entropy needs a probability density function, which can be approximated by kernel density estimation. We have investigated the proper sequence of procedures for combining the kernel density estimation and entropy estimation with a probability density function in order to calculate mutual information. Genotypes and their interactions were constructed to set the conditions for conditional entropy. Extensive simulation data created using three types of generating functions were analyzed using two different kernels as well as two types of multifactor dimensionality reduction and another probability density approximation method called m-spacing. The statistical power in terms of correct detection rates was compared. Using kernels was found to be most useful when the trait distributions were more complex than simple normal or gamma distributions. A full-scale genomic dataset was explored to identify associations using the 2-h oral glucose tolerance test results and γ-glutamyl transpeptidase levels as phenotypes. Clearly distinguishable single-nucleotide polymorphisms (SNPs) and interacting SNP pairs associated with these phenotypes were found and listed with empirical p-values.

Recursive Parameter estimation algorithm of the Probability (확률밀도함수의 축차모수추정 방법)

  • 한영열;박진수
    • Proceedings of the Korean Institute of Communication Sciences Conference
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    • 1984.04a
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    • pp.42-45
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    • 1984
  • we propose a new parameter estimation algorithm that converge with probability one and in mean square, If the mean is the function of parameter of the probability density function. This recursive algorithm is applicable also ever the parameters we estimate are multiparameter case. And the results are shown by the computer simulation.

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Monte Carlo Estimation of Multivariate Normal Probabilities

  • Oh, Man-Suk;Kim, Seung-Whan
    • Journal of the Korean Statistical Society
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    • v.28 no.4
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    • pp.443-455
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    • 1999
  • A simulation-based approach to estimating the probability of an arbitrary region under a multivariate normal distribution is developed. In specific, the probability is expressed as the ratio of the unrestricted and the restricted multivariate normal density functions, where the restriction is given by the region whose probability is of interest. The density function of the restricted distribution is then estimated by using a sample generated from the Gibbs sampling algorithm.

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Prediction of Land Use/Land Cover Change in Forest Area Using a Probability Density Function

  • Park, Jinwoo;Park, Jeongmook;Lee, Jungsoo
    • Journal of Forest and Environmental Science
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    • v.33 no.4
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    • pp.305-314
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    • 2017
  • This study aimed to predict changes in forest area using a probability density function, in order to promote effective forest management in the area north of the civilian control line (known as the Minbuk area) in Korea. Time series analysis (2010 and 2016) of forest area using land cover maps and accessibility expressed by distance covariates (distance from buildings, roads, and civilian control line) was applied to a probability density function. In order to estimate the probability density function, mean and variance were calculated using three methods: area weight (AW), area rate weight (ARW), and sample area change rate weight (SRW). Forest area increases in regions with lower accessibility (i.e., greater distance) from buildings and roads, but no relationship with accessibility from the civilian control line was found. Estimation of forest area change using different distance covariates shows that SRW using distance from buildings provides the most accurate estimation, with around 0.98-fold difference from actual forest area change, and performs well in a Chi-Square test. Furthermore, estimation of forest area until 2028 using SRW and distance from buildings most closely replicates patterns of actual forest area changes, suggesting that estimation of future change could be possible using this method. The method allows investigation of the current status of land cover in the Minbuk area, as well as predictions of future changes in forest area that could be utilized in forest management planning and policymaking in the northern area.

Estimation of Non-Gaussian Probability Density by Dynamic Bayesian Networks

  • Cho, Hyun-C.;Fadali, Sami M.;Lee, Kwon-S.
    • 제어로봇시스템학회:학술대회논문집
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    • 2005.06a
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    • pp.408-413
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    • 2005
  • A new methodology for discrete non-Gaussian probability density estimation is investigated in this paper based on a dynamic Bayesian network (DBN) and kernel functions. The estimator consists of a DBN in which the transition distribution is represented with kernel functions. The estimator parameters are determined through a recursive learning algorithm according to the maximum likelihood (ML) scheme. A discrete-type Poisson distribution is generated in a simulation experiment to evaluate the proposed method. In addition, an unknown probability density generated by nonlinear transformation of a Poisson random variable is simulated. Computer simulations numerically demonstrate that the method successfully estimates the unknown probability distribution function (PDF).

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