• Proceedings of the Korean Statistical Society Conference
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• 2003.10a
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• pp.161-166
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• 2003

In this paper, a new form of generalized linear models is proposed. The proposed models consist of a distribution function of the mean response and a weighted linear combination of distribution functions of covariates. This form addresses a structural problem of the link function in the generalized linear models. Markov chain Monte Carlo methods are used to estimate the parameters within a Bayesian framework.

• Korean Journal of Mathematics
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• v.22 no.4
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• pp.671-681
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• 2014

In this paper, we consider general Beta operators, which is a general sequence of integral type operators including Beta function. We study the King type Beta operators which preserves the third test function $x^2$. We obtain some approximation properties, which include rate of convergence and statistical convergence. Finally, we show how to reach best estimation by these operators.

• Communications for Statistical Applications and Methods
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• v.12 no.1
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• pp.169-179
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• 2005

In this study, we investigate the effects of the weight function in the bounded influence regression quantile (BIRQ) estimator for the AR(l) model with additive outliers. In order to down-weight the outliers of X -axis, the Mallows' (1973) weight function has been commonly used in the BIRQ estimator. However, in our Monte Carlo study, the BIRQ estimator using the Tukey's bisquare weight function shows less MSE and bias than that of using the Mallows' weight function or Huber's weight function. Thus, the use of the Tukey's weight function is recommended in the BIRQ estimator for our model.

• Communications for Statistical Applications and Methods
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• v.15 no.4
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• pp.509-516
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• 2008

We derive the influence function on the coefficient of variation. Empirical influence function and Sample influence function are used to verify the validity of the derived influence function. To show the validity of the influence function, we carry out simulations with random samples from normal distribution $N(20,1^2)$ and $N(20,5^2)$, respectively. The simulation result proves that the derived influence function is very accurate in estimating changes in the coefficient of variation when an observation is deleted.

• Journal of Ocean Engineering and Technology
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• v.7 no.2
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• pp.114-120
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• 1993

Responses of marine vehicles and ocean structures in a seaway can be predicted by applying the probabilistic approach. When we consider a linear system, the responses in a random seaway can be evaluated through spectral analysis in the frequency domain. But when we treat nonlinear system in irregular waves, it is necessary to get time history of waves. In the previous study we introduced one-directional waves (long crested waves)as wave environment and carried out calculations and experiments in the waves. But the real sea in which marine vehicles and structures are operated has multi-directional waves (short crested waves). It is important to get a simulated random sea and analyse dynamic problems in the sea. We need entire sample function or probabillty density function to infer statistical value of random process. However if the process are ergodic process, we can get statistical values by analysis of one sample function. In this paper, we developed the simulation technique of multi-directional waves and proved that the time history given by this method keep ergodic characteristics by the statistical analysis.

• The Journal of Korean Physical Therapy
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• v.11 no.2
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• pp.29-36
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• 1999

This study was carried out to compare the rotation between vestibular function and balance skills in normal and hearing-impaired children. The subjects were 20 normal children (8-10 years) and 20 bearing-impaired children (8-10 years). The SCPNT was used to assess vestibular function, then, one leg stance test was used to compare static balance skill of normal and hearing-impaired children according to existence of visual input and sex. The results were as follows: 1. In SCPNT, normal md hearing-impaired children showed statistical significance in all left-sided and right-sided rotations(p<.01), and the vestibular function responses of hearing-impaired children wore normal $20\%$, abnormal $45\%$, absent $35\%$. 2. To compare balance skills between normal and hearing-impaired according to eye open and eye close, one-leg stance Oat showed statistical significance in eye open(p<.05), but did not show statistical significance in eye close(p>.05). 3. SCPNT, ene-leg stance test did not show statistical significance according to sex(p>.05).

• The Journal of Korean Physical Therapy
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• v.12 no.1
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• pp.33-40
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• 2000

This study was carried out to compare the relation between vestibular function and balance skills in normal with heating-impaired children. The subjects were 20 normal children (8-10 years) and 20 hearing-impaired children (8-10 years). The SCPNT was used to assess vestibular function, then, functional reach test and backward walking test were usee to compare dynamic balance skills of normal and hearing-impaired children according to existence of visual input. The results were as follows : 1. In SCPNT, normal and hearing-impaired children showed statistical significance in all left-sided and right-sided rotations(p<.01), and the vestibular function responses of healing-impaired children were normal $20\%$, abnormal $45\%$, absent $35\%$. 2, To compare dynamic balance skills between normal and healing-impaired according to eye open and eye close, functional reach test did not show statistical significance in eye open situation(p>.05), but showed statistical significance in eye close situation(p<.05). 3. Backward walking test showed statistical significance in eye open and eye close situation(p<.01).

• Structural Engineering and Mechanics
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• v.86 no.3
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• pp.349-359
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• 2023

This paper presents a technique for determining the optimal number of elements in stochastic finite element analysis based on reliability analysis. Using the change-of-variable perturbation stochastic finite element approach, the probability density function of the dynamic responses of stochastic structures is explicitly determined. This method combines the perturbation stochastic finite element method with the change-of-variable technique into a united model. To further examine the relationships between the random fields, discretization of the random field parameters, such as the variance function and the scale of fluctuation, is also performed. Accordingly, the reliability index is calculated based on the explicit probability density function of responses with Gaussian or non-Gaussian random fields in any number of elements corresponding to the random field discretization. The numerical examples illustrate the effectiveness of the proposed method for a one-dimensional cantilever reinforced concrete column and a two-dimensional steel plate shear wall. The benefit of this method is that the probability density function of responses can be obtained explicitly without the use simulation techniques. Any type of random variable with any statistical distribution can be incorporated into the calculations, regardless of the restrictions imposed by the type of statistical distribution of random variables. Consequently, this method can be utilized as a suitable guideline for the efficient implementation of stochastic finite element analysis of structures, regardless of the statistical distribution of random variables.

• Journal of the Korean Statistical Society
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• v.22 no.2
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• pp.325-337
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• 1993

This paper propose two test statistics which enable us to proceed the variable selection in Fisher's linear discriminant function for the case of heterogeneous discrimination with equal training sample size. Simultaneous confidence intervals associated with the test are also given. These are exact and approximate results. The latter is based upon an approximation of a linear sum of Wishart distributions with unequal scale matrices. Using simulated sampling experiments, powers of the two tests have been tabulated, and power comparisons have been made between them.

• Communications for Statistical Applications and Methods
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• v.10 no.2
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• pp.305-317
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• 2003

We suggest methods to measure the changes in $x^2$ statistic when a row is deleted from a two-way contingency table. The influence function is extended and the deletion method is applied. Two examples are presented and we compare the results obtained from the influence function method and the deletion method.