• 제목/요약/키워드: Function

검색결과 69,513건 처리시간 0.074초

경험적 영향함수와 표본영향함수 간 차이 보정의 t통계량으로의 확장 (Extending the calibration between empirical influence function and sample influence function to t-statistic)

  • 강현석;김홍기
    • 응용통계연구
    • /
    • 제34권6호
    • /
    • pp.889-904
    • /
    • 2021
  • 본 연구는 Kang과 Kim (2020)의 후속 연구이다. 본 연구에서는 기존 연구에서 직접 유도하지 않았던 통계량의 표본영향함수를 유도한다. 그리고 이 결과를 바탕으로 경험적 영향함수와 표본영향함수는 어떠한 관계를 가지고 있는지 이론적으로 살펴보고, 경험적 영향함수를 통해 표본영향함수를 근사시켜 추정하는 방안에 대해 생각해 본다. 또한, 임의추출한 300개의 데이터를 바탕으로 모의실험을 통해 유도한 함수와 그 관계에 대한 그 타당성도 검증한다. 모의실험 결과 t통계량으로부터 유도한 표본영향함수와 경험적 영향함수와의 관계 및 경험적 영향함수를 통한 표본영향함수의 근사 방안에 대한 타당성도 검증해 냈다. 본 연구는 경험적 영향함수를 이용한 표본영향함수의 근사에서 오차를 줄이기 위한 방안을 제안하고 그 타당성을 검증하였으며, 이를 통해 기존의 연구에서 경험적 영향함수로 표본영향함수를 바로 근사시켰던 연구 방법에 효과적인 근사 방안을 제안한 점에서 의의를 갖는다.

Loss-of-function and Gain-of-function Rice Mutants from Gamma-Ray Mutagenesis

  • Lee, Seon-Woo;Park, Gyung-Ja;Kim, Jin-Cheol;Kim, Heung-Tae;Park, Yong-Ho;Cho, Kwang-Yun
    • The Plant Pathology Journal
    • /
    • 제19권6호
    • /
    • pp.301-304
    • /
    • 2003
  • Gamma-ray irradiation is known to induce various mutations in plants caused by chromosome alterations. This study investigated disease responses of selected gamma-ray induced rice mutants generated from seven Japonica-type rice cultivars against three plant diseases. Among the tested 22 mutants, three gain-of-function mutants and six loss-of-function mutants against rice blast were obtained, as well as three loss-of-function mutants against bacterial leaf blight (BLB). Two of the loss-of-function mutants were susceptible to both rice blast and BLB. Gain-of-function mutation has not been frequently observed in rice plants, thus, the mutants can be used to identify loci of novel genes for the regulation of disease resistant response.

역함수와의 교점을 구하는 과제에 대한 분석 (Analysis of the Tasks to Find Intersection Points of a Function and Its Inverse Function)

  • 허남구
    • 한국수학교육학회지시리즈A:수학교육
    • /
    • 제55권3호
    • /
    • pp.335-355
    • /
    • 2016
  • The purpose of this study is to analyze tasks to find intersection points of a function and its inverse function. To do this, we produced a task and 64 people solved the task. As a result, most people had a cognitive conflict related to inverse function. Because of over-generalization, most people regarded intersection points of a function and y=x as intersection points of a function and its inverse. To find why they used the method to find intersection points, we investigated 10 mathematics textbooks. As a result, 23 tasks were related a linear function, quadratic function, or irrational function. 21 tasks were solved by using an equation f(x)=x. 3 textbooks presented that a set of intersection points of a function and its inverse was not equal to a set of intersection points of a function and y=x. And there was no textbook to present that a set of intersection points of a function and its inverse was equal to a set of intersection points of $y=(f{\circ}f)(x)$ and y=x.

On the Radial Basis Function Networks with the Basis Function of q-Normal Distribution

  • Eccyuya, Kotaro;Tanaka, Masaru
    • 대한전자공학회:학술대회논문집
    • /
    • 대한전자공학회 2002년도 ITC-CSCC -1
    • /
    • pp.26-29
    • /
    • 2002
  • Radial Basis Function (RBF) networks is known as efficient method in classification problems and function approximation. The basis function of RBF networks is usual adopted normal distribution like the Gaussian function. The output of the Gaussian function has the maximum at the center and decrease as increase the distance from the center. For learning of neural network, the method treating the limited area of input space is sometimes more useful than the method treating the whole of input space. The q-normal distribution is the set of probability density function include the Gaussian function. In this paper, we introduce the RBF networks with the basis function of q-normal distribution and actually approximate a function using the RBF networks.

  • PDF

CERTAIN INTEGRAL FORMULAS ASSOCIATED WITH ALEPH (ℵ)-FUNCTION

  • Agarwal, Praveen;Jain, Shilpi;Karimov, Erkinjon T.;Prajapati, Jyotindra C.
    • 대한수학회논문집
    • /
    • 제32권2호
    • /
    • pp.305-319
    • /
    • 2017
  • Recently many authors have investigated so-called Aleph (${\aleph}$)-function and its various properties. Here, in this paper, we aim at establishing certain integral formulas involving the Aleph (${\aleph}$)-function. Precisely, integrals with product of Aleph (${\aleph}$)-function with Jacobi polynomials, Bessel Maitland function, general class of polynomials were under consideration. Some interesting special cases of our main result are also considered and shown to be connected with certain known ones.

Does a cognitive-exercise combined dual-task training have better clinical outcomes for the elderly people with mild cognitive impairment than a single-task training?

  • 박진혁
    • 재활치료과학
    • /
    • 제6권2호
    • /
    • pp.71-83
    • /
    • 2017
  • Objective: This study was to develop and verify the effects of the exercise-cognitive combined dual-task training program on cognitive function and depression of the elderly with mild cognitive impairment(MCI). Methods: The subjects were randomly assigned to the exercise-cognitive combined dual-task training group(n=32) or single-task training group(n=31). To identify the effects on cognitive function, general cognitive function, frontal lobe function, and attention/working memory were measured. Depression was evaluated using Korean version of Geriatric Depression Scale. The outcome measurements were performed before and after the 8 weeks of intervention(2 days per week). Results: After 8 weeks, general cognitive function, frontal cognitive function, attention/working memory function, depression of the dual-task training group were significantly increased than those of the single-task training group(p<0.05). Conclusion: The results indicated that an exercise-cognitive combined dual-task training for MCI was effective in improving general cognitive function, frontal /executive function, attention/working memory function and reducing depression.

A CHARACTERIZATION OF CONCENTRIC HYPERSPHERES IN ℝn

  • Kim, Dong-Soo;Kim, Young Ho
    • 대한수학회보
    • /
    • 제51권2호
    • /
    • pp.531-538
    • /
    • 2014
  • Concentric hyperspheres in the n-dimensional Euclidean space $\mathbb{R}^n$ are the level hypersurfaces of a radial function f : $\mathbb{R}^n{\rightarrow}\mathbb{R}$. The magnitude $||{\nabla}f||$ of the gradient of such a radial function f : $\mathbb{R}^n{\rightarrow}\mathbb{R}$ is a function of the function f. We are interested in the converse problem. As a result, we show that if the magnitude of the gradient of a function f : $\mathbb{R}^n{\rightarrow}\mathbb{R}$ with isolated critical points is a function of f itself, then f is either a radial function or a function of a linear function. That is, the level hypersurfaces are either concentric hyperspheres or parallel hyperplanes. As a corollary, we see that if the magnitude of a conservative vector field with isolated singularities on $\mathbb{R}^n$ is a function of its scalar potential, then either it is a central vector field or it has constant direction.

EXTENSION OF EXTENDED BETA, HYPERGEOMETRIC AND CONFLUENT HYPERGEOMETRIC FUNCTIONS

  • Choi, Junesang;Rathie, Arjun K.;Parmar, Rakesh K.
    • 호남수학학술지
    • /
    • 제36권2호
    • /
    • pp.357-385
    • /
    • 2014
  • Recently several authors have extended the Gamma function, Beta function, the hypergeometric function, and the confluent hypergeometric function by using their integral representations and provided many interesting properties of their extended functions. Here we aim at giving further extensions of the abovementioned extended functions and investigating various formulas for the further extended functions in a systematic manner. Moreover, our extension of the Beta function is shown to be applied to Statistics and also our extensions find some connections with other special functions and polynomials such as Laguerre polynomials, Macdonald and Whittaker functions.

A Non-Linear Exponential(NLINEX) Loss Function in Bayesian Analysis

  • Islam, A.F.M.Saiful;Roy, M.K.;Ali, M.Masoom
    • Journal of the Korean Data and Information Science Society
    • /
    • 제15권4호
    • /
    • pp.899-910
    • /
    • 2004
  • In this paper we have proposed a new loss function, namely, non-linear exponential(NLINEX) loss function, which is quite asymmetric in nature. We obtained the Bayes estimator under exponential(LINEX) and squared error(SE) loss functions. Moreover, a numerical comparison among the Bayes estimators of power function distribution under SE, LINEX, and NLINEX loss function have been made.

  • PDF