• 제목/요약/키워드: Statistical Model

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Bayesian Typhoon Track Prediction Using Wind Vector Data

  • Han, Minkyu;Lee, Jaeyong
    • Communications for Statistical Applications and Methods
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    • 제22권3호
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    • pp.241-253
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    • 2015
  • In this paper we predict the track of typhoons using a Bayesian principal component regression model based on wind field data. Data is obtained at each time point and we applied the Bayesian principal component regression model to conduct the track prediction based on the time point. Based on regression model, we applied to variable selection prior and two kinds of prior distribution; normal and Laplace distribution. We show prediction results based on Bayesian Model Averaging (BMA) estimator and Median Probability Model (MPM) estimator. We analysis 8 typhoons in 2006 using data obtained from previous 6 years (2000-2005). We compare our prediction results with a moving-nest typhoon model (MTM) proposed by the Korea Meteorological Administration. We posit that is possible to predict the track of a typhoon accurately using only a statistical model and without a dynamical model.

프랙탈 기법에 의한 울릉도 형상화 사례 연구 (Simulation Uleung Island By The Statistical Fractals)

  • 노용덕
    • 한국시뮬레이션학회논문지
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    • 제4권1호
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    • pp.113-119
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    • 1995
  • In 3D computer graphics, fractal techniques have been applied to terrain models. Even though fractal models have become popular for recreating a wide variety of the shapes found in nature, a specific 3D terrain model such as Uleung Island could not be formulated by statistical fractals easily owing to the random effects. However, by locating the midpoints on the edges and the surface of a specific terrain such as Uleung Island, a similar shape of the terrain model can be simulated. This paper shows the way of simulating 3D Uleung Island terrain model by the statistical fractals wherein the subdivision algorithm is used.

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Semiparametric Inference for a Multistate Stochastic Survival Model

  • Sung Chil Yeo
    • Communications for Statistical Applications and Methods
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    • 제5권1호
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    • pp.239-263
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    • 1998
  • In this paper, we consider a multistate survival model which incorporates covariates and contains two illness states and two death states. The underlying stochastic process is assumed to follow nonhomogeneous Markov process. The estimates of survival, transition and competing risks probabilities are given via the methods of partial likelihood and nonparametric maximum likelihood. Our discussion is based on the statistical theory of counting process. An illustration is given to the data of patients in a heart transplant program. The goodness of fit procedures are also discussed to check the adequacy of the model.

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AN SIRS EPIDEMIC MODEL ON A DISPERSIVE POPULATION

  • Ghosh, Asit K.;Chattopadhyay, J.;Tapaswi, P.K.
    • Journal of applied mathematics & informatics
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    • 제7권3호
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    • pp.925-940
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    • 2000
  • The spatial spread of a disease in an SIRS epidemic model with immunity imparted by subclinical infection on a population has been considered. The incidence rate of infection and the rate of immunization are both of nonlinear type. The dynamics of the infectious disease and its endemicity in local and global sense have been investigated.

Bootstrapping Logit Model

  • Kim, Dae-hak;Jeong, Hyeong-Chul
    • Communications for Statistical Applications and Methods
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    • 제9권1호
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    • pp.281-289
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    • 2002
  • In this paper, we considered an application of the bootstrap method for logit model. Estimation of type I error probability, the bootstrap p-values and bootstrap confidence intervals of parameter were proposed. Small sample Monte Carlo simulation were conducted in order to compare proposed method with existing normal theory based asymptotic method.

Binary Forecast of Heavy Snow Using Statistical Models

  • Sohn, Keon-Tae
    • Communications for Statistical Applications and Methods
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    • 제13권2호
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    • pp.369-378
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    • 2006
  • This Study focuses on the binary forecast of occurrence of heavy snow in Honam area based on the MOS(model output statistic) method. For our study daily amount of snow cover at 17 stations during the cold season (November to March) in 2001 to 2005 and Corresponding 45 RDAPS outputs are used. Logistic regression model and neural networks are applied to predict the probability of occurrence of Heavy snow. Based on the distribution of estimated probabilities, optimal thresholds are determined via true shill score. According to the results of comparison the logistic regression model is recommended.

Adaptive Watermark Detection Algorithm Using Perceptual Model and Statistical Decision Method Based on Multiwavelet Transform

  • Hwang Eui-Chang;Kim Dong Kyue;Moon Kwang-Seok;Kwon Ki-Ryong
    • 한국멀티미디어학회논문지
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    • 제8권6호
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    • pp.783-789
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    • 2005
  • This paper is proposed a watermarking technique for copyright protection of multimedia contents. We proposed adaptive watermark detection algorithm using stochastic perceptual model and statistical decision method in DMWT(discrete multi wavelet transform) domain. The stochastic perceptual model calculates NVF(noise visibility function) based on statistical characteristic in the DMWT. Watermark detection algorithm used the likelihood ratio depend on Bayes' decision theory by reliable detection measure and Neyman-Pearson criterion. To reduce visual artifact of image, in this paper, adaptively decide the embedding number of watermark based on DMWT, and then the watermark embedding strength differently at edge and texture region and flat region embedded when watermark embedding minimize distortion of image. In experiment results, the proposed statistical decision method based on multiwavelet domain could decide watermark detection.

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러프집합이론을 중심으로 한 감성 지식 추출 및 통계분석과의 비교 연구 (Knowledge Extraction from Affective Data using Rough Sets Model and Comparison between Rough Sets Theory and Statistical Method)

  • 홍승우;박재규;박성준;정의승
    • 대한인간공학회지
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    • 제29권4호
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    • pp.631-637
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    • 2010
  • The aim of affective engineering is to develop a new product by translating customer affections into design factors. Affective data have so far been analyzed using a multivariate statistical analysis, but the affective data do not always have linear features assumed under normal distribution. Rough sets model is an effective method for knowledge discovery under uncertainty, imprecision and fuzziness. Rough sets model is to deal with any type of data regardless of their linearity characteristics. Therefore, this study utilizes rough sets model to extract affective knowledge from affective data. Four types of scent alternatives and four types of sounds were designed and the experiment was performed to look into affective differences in subject's preference on air conditioner. Finally, the purpose of this study also is to extract knowledge from affective data using rough sets model and to figure out the relationships between rough sets based affective engineering method and statistical one. The result of a case study shows that the proposed approach can effectively extract affective knowledge from affective data and is able to discover the relationships between customer affections and design factors. This study also shows similar results between rough sets model and statistical method, but it can be made more valuable by comparing fuzzy theory, neural network and multivariate statistical methods.

The Confidence Intervals for Logistic Model in Contingency Table

  • Cho, Tae-Kyoung
    • Communications for Statistical Applications and Methods
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    • 제10권3호
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    • pp.997-1005
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    • 2003
  • We can use the logistic model for categorical data when the response variables are binary data. In this paper we consider the problem of constructing the confidence intervals for logistic model in I${\times}$J${\times}$2 contingency table. These constructions are simplified by applying logit transformation. This transforms the problem to consider linear form which called the logit model. After obtaining the confidence intervals for the logit model, the reverse transform is applied to obtain the confidence intervals for the logistic model.

A Study of a Combining Model to Estimate Quarterly GDP

  • Kang, Chang-Ku
    • 응용통계연구
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    • 제25권4호
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    • pp.553-561
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    • 2012
  • Various statistical models to Estimate GDP (measured as a nation's economic situation) have been developed. In this paper an autoregressive distributed lag model, factor model, and a Bayesian VAR model estimate quarterly GDP as a single model; the combined estimates were evaluated to compare a single model. Subsequently, we suggest that some combined models are better than a single model to estimate quarterly GDP.