• 한국수학교육학회지시리즈B:순수및응용수학
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• 제13권2호
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• pp.137-149
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• 2006

We introduce the notion of the generalized covariance and variance for bounded linear operators on Hilbert space, and prove that the generalized covariance-variance inequality holds. It turns out that the inequality is a useful formula in tile study of inequality involving linear operators in Hilbert spaces.

• International Journal of Fuzzy Logic and Intelligent Systems
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• 제9권1호
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• pp.1-3
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• 2009

Recently, Carlsson, Full\acute{e}$r and Majlender [1] presented the concept of possibilitic correlation representing an average degree of interaction between marginal distribution of a joint possibility distribution as compared to their respective dispersions. They also formulated the weak and strong forms of the possibilistic Cauchy-Schwarz inequality. In this paper, we define a new probability measure. Then the weak and strong forms of the Cauchy-Schwarz inequality are immediate consequence of probabilistic Cauchy-Schwarz inequality with respect to the new probability measure.

• Communications for Statistical Applications and Methods
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• 제21권3호
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• pp.201-212
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• 2014

We provide a simple basic method to find bounds for higher order moments of unimodal distributions in terms of lower order moments when the random variable takes value in a given finite real interval. The bounds for moments in terms of the geometric mean of the distribution are also derived. Both continuous and discrete cases are considered. The bounds for the ratio and difference of moments are obtained. The special cases provide refinements of several well-known inequalities, such as Kantorovich inequality and Krasnosel'skii and Krein inequality.

• 경영과학
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• 제28권1호
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• pp.159-167
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• 2011

The theory of random utility maximization (RUM) defines the probability of an alternative being chosen as the probability of its utility being perceived as higher than those of all the other competing alternatives in the choice set (Marschak 1960). According to this theory, consumers perceive the utility of an alternative not as a constant but as a probability distribution. Over the last two decades, there have been an increasing number of studies on the effect of utility variance on choice probability. The common result of the previous studies is that as the utility variance increases, the effect of the mean value of the utility (the deterministic component of the utility) on choice probability is reduced. This study provides a theoretical investigation on the effect of utility variance on choice probability without any assumptions on the specific forms of probability distributions. This study suggests that without assumptions of the probability distribution functions, firms cannot apply the marketing strategy of maximizing choice probability (or market share), but can only adopt the strategy of maximizing the minimum or maximum value of the expected choice probability. This study applies the Chebyshef inequality and shows how the changes in utility variances affect the maximum of minimum of choice probabilities and provides managerial implications.

• Journal of the Korean Society for Industrial and Applied Mathematics
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• 제2권2호
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• pp.49-56
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• 1998

In this paper, by the use of an Ostrowski type integral inequality for double integrals, we establish an upper bound for the estimation error variance of a continuous stream with stationary variogram.

• 산경연구논집
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• 제9권4호
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• pp.27-35
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• 2018

Purpose - The purpose of this research is to verify mediation effects of finance stress within relation structure between income inequality recognized by the elderly and life satisfaction. Research design, data, and methodology - In order to achieve the purpose of this research, we investigated recognition of income inequality of the elderly, finance stress and life satisfaction by using examination data aimed at 541 elderly people whose age is over 65 living in Chungcheongbuk-do. We conducted reliability, correlation, regression analysis_(tolerance limit and variance inflation factor) by using SPSS ver. 18.0. Results - From the result of analysis, it was proved that there are mediation effects of finance stress within the relation between income inequality recognized by the elderly and satisfaction with life. Based on this result, we suggest practical and political proposals to increase life satisfaction of the elderly. Conclusions - The purpose of this research is to verify mediation effects of finance stress in the relationship between income inequality and life satisfaction recognized by the elderly. From the result of research, first, a direct effect was discovered that as income inequality becomes high, life satisfaction will be decreased. Second, partial mediation effect of finance stress was confirmed in the relationship between income inequality and life satisfaction.

• 대한수학회지
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• 제39권4호
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• pp.495-507
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• 2002

In this paper, the characterization results related to Chernoff-type inequalities are applied for exponential-type (continuous and discrete) families. Upper variance bound is obtained here with a slightly different technique used in Alharbi and Shanbhag [1] and Mohtashami Borzadaran and Shanbhag [8]. Some results are shown with assuming measures such as non-atomic measure, atomic measure, Lebesgue measure and counting measure as special cases of Lebesgue-Stieltjes measure. Characterization results on power series distributions via Chernoff-type inequalities are corollaries to our results.

• 대한전기학회논문지:전력기술부문A
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• 제48권5호
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• pp.560-570
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• 1999

This paper formulates the suboptimal robust Kalman filtering problem into two coupled Linear Matrix Inequality (LMI) problems by applying Lyapunov theory to the augmented system which is composed of the state equation in the uncertain linear system and the estimation error dynamics. This formulations not only provide the sufficient conditions for the existence of the desired filter, but also construct the suboptimal robust Kalman filter. The proposed filter can guarantee the optimized upper bound of the estimation error variance for uncertain systems with parametric uncertainties in both the state and measurement matrices. In addition, this paper shows how the problem of finding the minimizing solution subject to Quadratic Matrix Inequality (QMI), which cannot be easily transformed into LMI using the usual Schur complement formula, can be successfully modified into a generic LMI problem.

• 디지털융복합연구
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• 제17권1호
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• pp.55-62
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• 2019

본 연구는 주택가격의 변화가 거시경제변수와 소득불평등에 영향을 미치는 중요한 요인으로 작용하였을 것으로 판단하여 주택 전세가격과 매매가격, 지니계수, 금리, 취업자수와의 관계를 분석하였다. 2003년부터 2016년까지 국내 16개 광역시 도의 자료를 활용한 패널분석을 하였고 패널자료임을 감안하여 패널 VAR모형을 구축한 뒤 그랜저인과관계, 충격반응함수, 분산분해분석을 실시하였다. 그랜저인과성 검사와 충격반응검사 결과, 주택시장의 매매가격과 취업자수, 금리가 소득불평등에 유의한 영향을 미치는 것으로 나타났다. 글로벌 금융위기 이전에는 전세가격만이 통계적으로 유의한 결과를 보였지만 금융위기 이후에는 주택 전세가격과 매매가격이 유의한 영향을 미치는 것으로 나타났다. 또한 분산분해분석 결과에서는 금융위기 이전에는 전세가격이 소득불평등에 미치는 영향력이 크게 나타난 반면에 금융위기 이후에는 전세가격의 영향력이 낮아지고 금리가 큰 영향을 미치는 것으로 나타나, 금리, 취업자수, 주택시장의 매매가격과 전세가격이 소득불평등에 주요한 요인으로 작용할 수 있다는 것으로 확인되었다. 따라서 정부의 부동산 정책을 비롯한 경제 활성화를 위한 정책시 변수들간의 영향력을 고려하여 소득불평등을 완화시킬 수 있는 정책수립이 될 수 있길 기대한다.

• 한국지능시스템학회논문지
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• 제22권5호
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• pp.549-554
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• 2012

본 논문에서는 추정 분산 제약을 갖는 비선형 이산시간에 대한 최적의 퍼지 필터에 대한 내용을 다루고자 한다. 필터를 설계할 때, 추정오차의 분산값은 필터의 성능이 결정하는 변수중 하나다. 이런 분산값에 더욱 강인한 필터를 설계하고자, 분산 제약 조건을 주어 필터를 설계하고자 한다. 먼저, 비선형 모델을 Tagaki-Sugeno 퍼지 모델을 이용하여 선형 모델로 변형한 후, 이 모델을 기반으로 선형 필터를 디자인한다. 이때 필터설계 과정 중 필터의 각 파라미터값을 구하기 위해 상태 추정오차 값은 평균제곱에 제한되며, 상태오차의 정상상태 분산값은 각각의 미리 정한 상한 제한 값 보다 작은 조건에서 필터를 설계하여 선형행렬부등식과 대수 이차 행렬부등식을 이용하여 파라미터값을 구한다. 이렇게 설계된 퍼지 필터는 트럭트레일러 시뮬레이션을 통해 설계 과정과 성능을 보여준다.