• Journal of the Korean Data and Information Science Society
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• v.15 no.4
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• pp.921-934
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• 2004

We consider the problem of identifying and testing outliers in linear regression. First, we consider the scale-ratio tests for testing the null hypothesis of no outliers. A test based on the ratio of two residual scale estimates is proposed. We show the asymptotic distribution of test statistics and investigate the properties of the test. Next we consider the problem of identifying the outliers. A forward procedure based on the suggested test is proposed and shown to perform fairly well. The forward procedure is unaffected by masking and swamping effects because the test statistics used a robust scale estimate.

• Korean Journal of Veterinary Research
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• v.53 no.2
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• pp.73-76
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• 2013

The aim of this study was to produce a simple and inexpensive technique for estimating the obturator foramen area (OFA) from young calves based on the hypothesis that OFA can be extrapolated from simple linear measurements. Three linear measurements - dorsoventral height, craneocaudal width and total perimeter of obturator foramen - were obtained from 55 bovine hemicoxae. Different algorithms for determining OFA were then produced with a regression analysis (curve fitting) and statistical analysis software. The most simple equation was OFA ($mm^2$) = [3,150.538 + ($36.111^*CW$)] - [147,856.033/DH] (where CW = craneocaudal width and DH = dorsoventral height, both in mm), representing a good nonlinear model with a standard deviation of error for the estimate of 232.44 and a coefficient of multiple determination of 0.846. This formula may be helpful as a repeatable and easily performed estimation of the obturator foramen area in young bovines. The area of the obturator foramen magnum can thus be estimated using this regression formula.

• Computers and Concrete
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• v.23 no.5
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• pp.303-309
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• 2019

This study investigates axisymmetric fractional vibration of an isotropic hyperelastic semi-linear thin disc with a view to examine effects of finite deformation associated with the material of the disc and effects of fractional vibration associated with the motion of the disc. The generalized three-dimensional equation of motion is reduced to an equivalent time fraction one-dimensional vibration equation. Using the method of variable separable, the resulting equation is further decomposed into second-order ordinary differential equation in spatial variable and fractional differential equation in temporal variable. The obtained solution of the fractional vibration problem under consideration is described by product of one-parameter Mittag-Leffler and Bessel functions in temporal and spatial variables respectively. The obtained solution reduces to the solution of the free vibration problem in literature. Finally, and amongst other things, the Cauchy's stress distribution in thin disc under finite deformation exhibits nonlinearity with respect to the displacement fields whereas in infinitesimal deformation hypothesis, these stresses exhibit linear relation with the displacement field.

• Journal of Technology Innovation
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• v.14 no.1
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• pp.255-276
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• 2006

This study aims to investigate hypotheses for the effects of leaders' individualized consideration leadership behaviors(Bass, 1985) and employee's organizational commitment. It is proposed that individualized consideration leadership behaviors will positively effect on employee's organizational commitment. And to understand the importance of followers' characteristics in recent leadership studies, it is also proposed that the follower's need for achievement(N-Arch) moderates in the relationship of individualized consideration leadership behaviors and organizational commitment. After descriptive survey, research model setup, and field survey, this empirical study investigated the above mentioned hypotheses thru SPSS for Windows 12.0. It involved linear regression analysis to reveal the significant main effect of the individualized consideration leadership behaviors. It also revealed moderating regression analysis to reveal the significant moderating effects of need for achievement between the independent variables(individualized consideration leadership behaviors) and dependent variable(the organizational commitment). Results revealed that leaders' individualized consideration leadership behaviors positively affected to its employee's organizational commitment(Hypothesis 1). And positive moderating effect of N-Arch was strongly supported between leader's individualized consideration leadership behaviors and follower's organizational commitment (Hypothesis 2).

• Transactions of the Korean Society of Mechanical Engineers B
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• v.30 no.7 s.250
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• pp.671-681
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• 2006

This study focuses on the development of numerical procedure to analyze the nonlinear combustion instabilities in liquid rocket engine. Nonlinear behaviors of acoustic instabilities are characterized by the existence of limit cycle in linearly unstable engines and nonlinear or triggering instability in linearly stable engines. To discretize convective fluxes with high accuracy and robustness, approximated Riemann solver based on characteristics and Euler-characteristic boundary conditions are employed. The present procedure predicts well the transition processes from initial harmonic pressure disturbance to N-like steep-fronted shock wave in a resonant pipe. Longitudinal pressure oscillations within the SSME(Space Shuttle Main Engine) engine have been analyzed using the pressure-sensitive time lag model to account for unsteady combustion response. It is observed that the pressure oscillations reach a limit cycle which is independent of the characteristics of the initial disturbances and depends only on combustion parameters and operating conditions.

• Journal of Labour Economics
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• v.24 no.1
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• pp.231-251
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• 2001

In this study I attempted to compare the two contrasting theories on life satisfaction; alsolute or relative. I could confirm a positive curve-linear relationship of income and life satisfaction among Koreans as in many previous studies. A relative hypothesis saying that one's relative superiority on education could bring about more satisfaction was partly supported in this study. On the other hand, another relative hypothesis saying that income increase could make more satisfaction than income decrease over time on a identical level of income was rejected. This result suggests that income increase can not give more satisfaction in addition to more affluence simply because of the fact that one's current income is higher than his or her previous level of income.

• Communications for Statistical Applications and Methods
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• v.24 no.6
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• pp.663-671
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• 2017

Some genetic association tests include an unidentifiable nuisance parameter under the null hypothesis of no association. When the mode of inheritance (MOI) is not specified in a case-control design, the Cochran-Armitage (CA) trend test contains an unidentifiable nuisance parameter. The transmission disequilibrium test (TDT) in a family-based association study that includes the unaffected also contains an unidentifiable nuisance parameter. The hypothesis tests that include an unidentifiable nuisance parameter are typically performed by taking a supremum of the CA tests or TDT over reasonable values of the parameter. The p-values of the supremum test statistics cannot be obtained by a normal or chi-square distribution. A common method is to use a Davies's upper bound of the p-value instead of an exact asymptotic p-value. In this paper, we provide a unified sine-cosine process expression of the CA trend test that does not specify the MOI and the TDT that includes the unaffected. We also present a closed form expression of the exact asymptotic formulas to calculate the p-values of the supremum tests when the score function can be written as a linear form in an unidentifiable parameter. We illustrate how to use the derived formulas using a pharmacogenetics case-control dataset and an attention deficit hyperactivity disorder family-based example.

• The Journal of Asian Finance, Economics and Business
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• v.7 no.10
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• pp.161-169
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• 2020

The condition of mining companies that exploit natural resources in their business processes underline this research to emphasize on social and environmental issues. After twelve years of government regulation on CSR practices, this study investigates the factors that influence mining companies in disclosing information about corporate social responsibility based on legitimacy, stakeholders, and agency theory. Thus, independent variables are foreign ownership, company size, leverage, and the board of commissioners. The dependent variable is the corporate social reporting disclosure that is measured using GRI indexing. For sampling, we have used thirty-four Indonesian mining companies listed in IDX during the 2014-2018. out of which only fifty-two companies meet the sample criteria. All data should pass the classical assumption test to get the best estimator. Multiple linear regression is used to test the hypothesis, and the results show that the model is good, and can explain 60% of the dependent variable. Based on F-test, all four variables affect CSR practices simultaneously. The findings of this study suggest that foreign ownership and firm size influences CSR disclosure in a positive direction. However, this study did not support the hypothesis that leverage negatively affects CSR disclosure and board size measures positively affect CSR disclosure.

• The Journal of Asian Finance, Economics and Business
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• v.7 no.10
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• pp.795-802
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• 2020

This study seeks to determine the effect of the application of accounting information system (AIS), internal control system, and human resource (HR) competency on the quality of local government financial statements (FS). This study uses agency theory and compliance theory. Agency theory is used to explain that there is a link between the society as the principal and the government as the agent. Compliance theory is a theory, which states that every agency is obliged to comply with regulations because the law-drafting authority has the right to dictate behavior. The population in this study were employees of the financial division of local government organizations in one of the districts in Central Java, Indonesia. The total samples in this study was 106 respondents. The data used are primary data taken from distributing questionnaires to respondents. The method of analysis used to test the hypothesis was multiple linear regression analysis. The results of hypothesis testing indicate that HR competency has an effect on the quality of FS; however, the application of AIS and internal control system has no effect on the quality of FS. The implication of this research underlines the importance of HR competency to improve the quality of local government FS.

• Journal of the Korean Home Economics Association
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• v.31 no.1
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• pp.121-135
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• 1993

This study was to investigate the relationship between the level of life satisfaction of middle-aged woman and that of the family cohesion and adaptibility, the subjects were 243 married women aged from 40 to 59 years old. The survey instruments were Life Satisfaction Scale and FACESⅢ by using SPSSPC+ program package, especially ANOVA, Scheffe's test, Correlation and Stepwise Multiple Regression. The results were as follows; 1. The overall levels of life satisfaction were middling. 2. The family cohesions were relatively high, adaptibility middling. 3. 1) The levels of life satisfaction were different according to their ages, frequencies of leisure activities, and levels of household income. 2) The levels of life satisfaction were different according to the levels of the family adaptibility and cohesion. 3) Dividing the family type into tow part by the levels of cohesion and adaptibility, the levels of life satisfaction had no differences in typeⅠ based on curvilinea hypothesis, but those of life satisfaction had differences in typeⅡ on linear hypothesis. 4. The results of stepwise multiple regression ; the variables having an effects on the level of life satisfaction were revealed cohesion, frequencies of leisure activities, and the level of household income, and their explanatory power 33%.