• 응용통계연구
• /
• 제7권2호
• /
• pp.239-248
• /
• 1994

지수혼합 시계열 모형인 EARMA(1,1) 모형이 율-워커 추정법과 조건최소제곱 추정법으로 추정되었다. 율-워커 추정량은 이동평균모수가 포함된 ERAMA(1,1) 모형인 경우 유일하지 못하므로 가역 조건을 만족하는 추정량이 유일한 추정량으로 얻어졌고, 조건최소제곱 추정량은 근사추정량이 얻어졌다. 모의 실험을 통하여 근사조건제곱 추정량은 율-워커 추정량보다 평균제곱오차면에서 훨씬 좋은 추정량으로 나타났다.

• Communications for Statistical Applications and Methods
• /
• 제14권3호
• /
• pp.667-677
• /
• 2007

In this paper, we propose a method for estimating the mean of a population which has a linear trend, when both n, the sample size, and k, the reciprocal of the sampling fraction, are odd numbers. The proposed method, not having the drawbacks of centered systematic sampling, centered modified sampling and centered balanced sampling, consists of selecting a sample by balanced systematic sampling and estimating the population mean by using interpolation. We compare the efficiency of the proposed method and existing methods under the criterion of the expected mean square error based on the infinite superpopulation model.

• KSII Transactions on Internet and Information Systems (TIIS)
• /
• 제7권8호
• /
• pp.2010-2026
• /
• 2013

The combination of biometrics and cryptography gains a lot of attention from both academic and industry community. The noisy biometric measurement makes traditional identity based cryptosystems unusable. Also the extraction of key from biometric information is difficult. In this paper, we propose an efficient biometric identity based signature scheme (Bio-IBS) that makes use of fuzzy extractor to generate the key from a biometric data of user. The component fuzzy extraction is based on error correction code. We also prove that the security of suggested scheme is reduced to computational Diffie-Hellman (CDH) assumption instead of other strong assumptions. Meanwhile, the comparison with existing schemes shows that efficiency of the system is enhanced.

• East Asian mathematical journal
• /
• 제27권3호
• /
• pp.319-337
• /
• 2011

We approximate a locally unique solution of a nonlinear equation in a Banach space setting using an inexact two-step Newton-type method. It turn out that under our new idea of recurrent functions, our semilocal analysis provides tighter error bounds than before, and in many interesting cases, weaker sufficient convergence conditions. Applications including the solution of nonlinear Chandrasekhar-type integral equations appearing in radiative transfer and two point boundary value problems are also provided in this study.

• 한국수학교육학회지시리즈D:수학교육연구
• /
• 제10권3호
• /
• pp.169-187
• /
• 2006

Ubiquitous errors in algebra like $(x+y)^2=x^2+y^2$ are a constant reminder that most students' manipulation of algebraic symbols has become detached from structural principles. The U.S. mathematics education community (NCTM, 2000) has responded by shying away from algebra as a structural study, preferring instead to ground meaning in empirical domains of reference. A new analysis of such errors shows that students' detachment from structural meaning stems from an inadequate structural curriculum, not from the inherent difficulty of adopting an abstract perspective on expressions and equations. A structural curriculum is outlined that preserves the possibility of students' engaging fully with algebra as both an empirical and a structural study.

• Journal of the Korean Data and Information Science Society
• /
• 제17권3호
• /
• pp.871-888
• /
• 2006

Many studies have been done to develop procedures to deal with missing values. Most common method is to reassign the other values to the missing data. The purpose of our study is to suggest adjusted Cohen methods and to compare the efficiency of them with other methods through a simulation study. The adjusted Cohen methods use an auxiliary variable to arrange ranking of the variable with missing values. It leads to a reduced mean square error(MSE) compared with the Cohen method.

• Journal of the Korean Statistical Society
• /
• 제19권2호
• /
• pp.113-121
• /
• 1990

Let ${X_n : n=1,2,\cdots}$ be iid random variables with distribution $P_{\theta}, \theta \in H$ where $H$ is some abstract parameter space. We consider a sequential confidence interval I for the mean $\mu = \mu(\theta)$ of $P_{\theta}$ satisfying $P_{\theta}(\mu \in I) \geq 1-\alpha$ and $P_{\theta}(\mu-\delta(\mu) \in I) \leq \beta$ for all $\theta \in H$ for any given an imprecision real valued function $\delta(\mu) > 0$ and error probabilities $0 < \alpha, \beta < 1$. A one-sided sequential confidence interval is constructed under some restriction of the family {P_{\theta} : \theta \in H}$ and the imprecision function $\delta$. This is extended to the two-sided cases.

• Communications for Statistical Applications and Methods
• /
• 제27권4호
• /
• pp.469-486
• /
• 2020

Entropy is an important term in statistical mechanics that was originally defined in the second law of thermodynamics. In this paper, we consider the maximum likelihood estimation (MLE), maximum product spacings estimation (MPSE) and Bayesian estimation of the entropy of an inverse Weibull distribution (InW) under a generalized type I progressive hybrid censoring scheme (GePH). The MLE and MPSE of the entropy cannot be obtained in closed form; therefore, we propose using the Newton-Raphson algorithm to solve it. Further, the Bayesian estimators for the entropy of InW based on squared error loss function (SqL), precautionary loss function (PrL), general entropy loss function (GeL) and linex loss function (LiL) are derived. In addition, we derive the Lindley's approximate method (LiA) of the Bayesian estimates. Monte Carlo simulations are conducted to compare the results among MLE, MPSE, and Bayesian estimators. A real data set based on the GePH is also analyzed for illustrative purposes.

• 한국수학교육학회지시리즈B:순수및응용수학
• /
• 제12권4호
• /
• pp.275-287
• /
• 2005

Geometric invariants are basic tools for geometric processing and computer vision. In this paper, we give a linear approximation for the differentiation of the binormal vector field of a space curve by using the forward and backward differences of discrete binormal vectors. Two kind of discrete torsion, say, back-ward torsion $T_b$ and forward torsion $T_f$ can be defined by the dot product of the (backward and forward) discrete differentiation of binormal vectors that are linear approximations of torsion. Using Frenet formula and Taylor series expansion, we give error estimations for the discrete torsions. We also give numerical tests for a curve. Notably the average of $T_b$ and $T_f$ looks more stable in errors.

• 한국수학교육학회지시리즈C:초등수학교육
• /
• 제6권1호
• /
• pp.1-10
• /
• 2002

The objectives of the current study are on the practical use of geoboard in an elementary school class. To do this, we first investigate how come geoboard is significant in a practical use. Second, we present an example of practical use of geoboard connecting with the analysis of the 7th curriculum. Third, we investigate the results of geoboard which is applied to elementary school class. The results of this research are as follows: First, the instruction of using geoboard can give an interest and curiosity to all students. Second, right triangle, rectangle, square and so on can be easily constructed because geoboard is linked by dots. Third, by constructing figures on geoboard and comparing figures which is made by themselves, students could better understand the concept of figures rather than the explanation of teacher. fourth, students can be improved the ability of problem solving and spatial sense by providing experience for exploration. Fifth, students need not to have anxiety for error because geoband is used and so can be corrected easily.