• Title/Summary/Keyword: additive model

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A Generalized Partly-Parametric Additive Risk Model

  • Park, Cheol-Yong
    • Journal of the Korean Data and Information Science Society
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    • v.17 no.2
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    • pp.401-409
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    • 2006
  • We consider a generalized partly-parametric additive risk model which generalizes the partly parametric additive risk model suggested by McKeague and Sasieni (1994). As an estimation method of this model, we propose to use the weighted least square estimation, suggested by Huffer and McKeague (1991), for Aalen's additive risk model by a piecewise constant risk. We provide an illustrative example as well as a simulation study that compares the performance of our method with the ordinary least squares method.

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Hydration Model of Ettringite-Gypsum Type Expansive Additive (에트링가이트-석회 복합계 팽창재의 수화반응 모델화)

  • Park Sun Gyu;Noguchi Takahumi;Song Ha Won;Kim Moo Han
    • Proceedings of the Korea Concrete Institute Conference
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    • 2004.11a
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    • pp.683-686
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    • 2004
  • In recent years, some attention was particularly given to cracking sensitivity of high performance concrete. It has been argued and demonstrated experimentally that such concrete undergoes autogenous shrinkage due to self-desiccation at early age, and, as a result, internal tensile stress may develop, leading to micro cracking and macro cracking. One possible method to reduce cracking due to autogenous shrinkage is the addition of expansive additive. Tests conducted by many researches have shown the beneficial effects of addition of expansive additive for reducing the risk of shrinkage-introduced cracking. However, the research on hydration model of expansion additive has been hardly researched up to now. This paper presents a study of the hydration model of Ettringite-Gypsum type expansive additive. Result of comparing forecast values with experiment value, proposed model is shown to expressible of hydration of expansive additive.

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Checking the Additive Risk Model with Martingale Residuals

  • Myung-Unn Song;Dong-Myung Jeong;Jae-Kee Song
    • Journal of the Korean Statistical Society
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    • v.25 no.3
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    • pp.433-444
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    • 1996
  • In contrast to the multiplicative risk model, the additive risk model specifies that the hazard function with covariates is the sum of, rather than product of, the baseline hazard function and the regression function of covariates. We, in this paper, propose a method for checking the adequacy of the additive risk model based on partial-sum of matingale residuals. Under the assumed model, the asymptotic properties of the proposed test statistic and approximation method to find the critical values of the limiting distribution are studied. Several real examples are illustrated.

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A Nonparametric Additive Risk Model Based on Splines

  • Park, Cheol-Yong
    • Journal of the Korean Data and Information Science Society
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    • v.18 no.1
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    • pp.97-105
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    • 2007
  • We consider a nonparametric additive risk model that is based on splines. This model consists of both purely and smoothly nonparametric components. As an estimation method of this model, we use the weighted least square estimation by Huller and Mckeague (1991). We provide an illustrative example as well as a simulation study that compares the performance of our method with the ordinary least square method.

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A Nonparametric Additive Risk Model Based On Splines

  • Park, Cheol-Yong
    • 한국데이터정보과학회:학술대회논문집
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    • 2006.11a
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    • pp.49-50
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    • 2006
  • We consider a nonparametric additive risk model that are based on splines. This model consists of both purely and smoothly nonparametric components. As an estimation method of this model, we use the weighted least square estimation by Huffer and McKeague (1991). We provide an illustrative example as well as a simulation study that compares the performance of our method with the ordinary least square method.

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An Additive Quantitative Randomized Response Model by Cluster Sampling

  • Lee, Gi-Sung
    • The Korean Journal of Applied Statistics
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    • v.25 no.3
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    • pp.447-456
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    • 2012
  • For a sensitive survey in which the population is comprised of several clusters with a quantitative attribute, we present an additive quantitative randomized response model by cluster sampling that adapts a two-stage cluster sampling instead of a simple random sample based on Himmelfarb-Edgell's additive quantitative attribute model and Gjestvang-Singh's one. We also derive optimum values for the number of 1st stage clusters and the optimum values of observation units in a 2nd stage cluster under the condition of minimizing the variance given constant cost. We can see that Himmelfarb-Edgell's model is more efficient than Gjestvang-Singh's model under the condition of cluster sampling.

A General Semiparametric Additive Risk Model

  • Park, Cheol-Yong
    • Journal of the Korean Data and Information Science Society
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    • v.19 no.2
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    • pp.421-429
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    • 2008
  • We consider a general semiparametric additive risk model that consists of three components. They are parametric, purely and smoothly nonparametric components. In parametric component, time dependent term is known up to proportional constant. In purely nonparametric component, time dependent term is an unknown function, and time dependent term in smoothly nonparametric component is an unknown but smoothly function. As an estimation method of this model, we use the weighted least square estimation by Huffer and McKeague (1991). We provide an illustrative example as well as a simulation study that compares the performance of our method with the ordinary least square method.

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On a Detection Scheme for Weak Deterministic Signals in Non-Additive Noise (비가산성 잡음에서의 약한 화정적 신호의 검파방식에 관하여)

  • Song, Iick-Ho
    • Journal of the Korean Institute of Telematics and Electronics
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    • v.25 no.9
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    • pp.1019-1026
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    • 1988
  • A parametric detection scheme for determenistic signals is obtained in a generalized observation model which contains non-additive noise. The model employed in this paper includes several special cases such as those describing purely-additive noise, multiplicative noise, and signal dependent noise and allows the consideration of deterministic and random signals. Locally optimum detectors for known deterministic signals in the model are derived and analyzed for performance. It is shown that the locally optimum detectors are interesting generalizations of those for the purely-additive noise model. Performance of the locally optimum detectors designed for the generalized observation model is compared to that of other common detectors.

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Estimation of Additive and Dominance Genetic Variances in Line Breeding Swine

  • Ishida, T.;Kuroki, T.;Harada, H.;Fukuhara, R.
    • Asian-Australasian Journal of Animal Sciences
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    • v.14 no.1
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    • pp.1-6
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    • 2001
  • Additive and dominance genetic variances were estimated for purebred Landrace selected with line breeding from 1989 to 1995 at Miyazaki Livestock Experiment Station, Kawaminami Branch. Ten body measurements, two reproductive traits and fifteen carcass traits were analyzed with single-trait mixed model analysis. The estimates of narrow-sense heritabilities by additive model were in the range of 0.07 to 0.46 for body measurements, 0.05 to 0.14 for reproductive traits, and 0.05 to 0.68 for carcass traits. The additive model tended to slightly overestimate the narrow-sense heritabilities as compared to the additive and dominance model. The proportion of the dominance variance to total genetic variance ranged from 0.11 to 0.91 for body measurements, 0.00 to 0.65 for reproductive traits, and 0.00 to 0.86 for carcass traits. Large differences among traits were found in the ratio of dominance to total genetic variance. These results suggested that dominance effect would affect the expression of all ten body measurements, one reproductive trait, and nine carcass traits. It is justified to consider the dominance effects in genetic evaluation of the selected lines for those traits.

A Test Procedure for Right Censored Data under the Additive Model

  • Park, Hyo-Il;Hong, Seung-Man
    • Communications for Statistical Applications and Methods
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    • v.16 no.2
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    • pp.325-334
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    • 2009
  • In this research, we propose a nonparametric test procedure for the right censored and grouped data under the additive hazards model. For deriving the test statistics, we use the likelihood principle. Then we illustrate proposed test with an example and compare the performance with other procedure by obtaining empirical powers. Finally we discuss some interesting features concerning the proposed test.