• Communications for Statistical Applications and Methods
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• v.11 no.3
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• pp.643-655
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• 2004

L$_1$-estimator in the linear regression model is widely recognized to have superior robustness in the presence of vertical outliers. While the L$_1$-estimation procedures and algorithms have been developed quite well, less progress has been made with the hypothesis test in the multiple L$_1$-regression. This article suggests computer-intensive resampling approaches, jackknife and bootstrap methods, to estimating the variance of L$_1$-estimator and the scale parameter that are required to compute the test statistics. Monte Carlo simulation studies are performed to measure the power of tests in small samples. The simulation results indicate that bootstrap estimation method is the most powerful one when it is employed to the likelihood ratio test.

• Management & Information Systems Review
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• v.2
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• pp.237-266
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• 1998

The purpose of this study was to analyze the differences of application level the computer programming languages in major. The method of this study is the empirical method based on theoretical one with the previous bibliographical suduies. The sample consists of 268 listed university disclosing over the period of Dec. 1. 1997 to Du. 15. 1997. The samples were 10 university in university of Seoul, Pusan, Masan City, Korea. The data were collected by questionnaire research through interview with each person. The analysis data was carried to 268 samples by using SPSS/PC for Windows Version 7.5 statistical package. Statistical methods such as frequency analysis, chi-square test, ANOVA test, correlation analysis were used to test the research questions. This paper focuses on the design of the hypothesis test show that the 2 type are significantly different in major of university students. Before the test of research questions performed it frequency analysis by using the factor score that bring each items. The research type of 2 guoups, that is, BA Group(business administration group) and NBA Group(non-business administration guoup). To summarize the result of this study is as follows ; (1) Hypothesis 1 : Concerning about computer programming language in major, the significant difference is application the present condition. (2) Hypothesis 2 : Concerning about computer programming language in major, the significant difference is application level. (3) Hypothesis 3 : Concerning about each application software in major, the significant difference is application level. According to the results of this study, it is found that (1) Hypothesis 1 related In application the present condition of computer programming language was accepted its all at 0.05 % significance level. (2) Hypothesis 2 related to application level of computer programming language was accepted its all at 0.05 % significance level. (3) Hypothesis 3 related to application level of each application software was rejected its all. at 0.05 % significance level.

• The Korean Journal of Applied Statistics
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• v.24 no.2
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• pp.239-251
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• 2011

The need for statistical analysis to discern the existence and the type of international business comovement has increased as business and economic variations in one country is directly transmitted to business and financial market conditions in another without a long lag. This study performs the statistical tests for th locomotive hypothesis to understand the structural character of the long-run mechanism among Korea-US current and future business movements and the domestic stock market. The U.S. future business prospect, rather than the US current and the domestic current and future business conditions, appears to signi cantl a ect the domestic stock market movement.

• Journal of the Korea Fashion and Costume Design Association
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• v.22 no.3
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• pp.89-98
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• 2020

The survey targeted 270 men and women in their from their 20s-50s who live in Seoul and Gyeonggi-do. The purpose of this study was to investigate the effect of the vocation of beauty worker on job satisfaction and self-development. The questionnaire was administered from January 5th to March 10th, 2020, and 243 responses were used for statistical analysis. 27 unanswered or unfaithful questionnaires were disregarded. Using SPSS WIN 21.0 was applied for statistical processing. First, the data was analyzed using descriptive statistical analysis, factor analysis, and reliability verification, For validity verification, one-way variance analysis, correlation analysis, and simple regression analysis were used. The results of this study are as follows. First, upon examining the hypothesis that vocation has a positive (+) effect on job satisfaction, a significant positive (+) influence was shown, and it was found that it was determined vocation is an important factor in job satisfaction for beauty industry professionals. Second, upon examining the hypothesis that vocation has a positive (+) effect on self- development, a significant positive (+) correlation was found between the self-development of beauty industry professionals and job satisfaction. Third, upon examining the hypothesis that occupational vocation has a positive (+) effect on self- development, a significant positive (+) correlation was shown between self-development and job satisfaction of beauty industry professionals.

• Proceedings of the Korean Society for Noise and Vibration Engineering Conference
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• 2014.10a
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• pp.347-349
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• 2014

Model verification and validation (V&V) is a current research topic to build computational models with high predictive capability by addressing the general concepts, processes and statistical techniques. The hypothesis test for validity check is one of the model validation techniques and gives a guideline to evaluate the validity of a computational model when limited experimental data only exist due to restricted test resources (e.g., time and budget). The hypothesis test for validity check mainly employ Type I error, the risk of rejecting the valid computational model, for the validity evaluation since quantification of Type II error is not feasible for model validation. However, Type II error, the risk of accepting invalid computational model, should be importantly considered for an engineered products having high risk on predicted results. This paper proposes a technique named as the response-adaptive experimental design to reduce Type II error by adaptively designing experimental conditions for the validation experiment. A tire tread block problem and a numerical example are employed to show the effectiveness of the response-adaptive experimental design for the validity evaluation.

• Journal of the Korean Home Economics Association
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• v.32 no.2
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• pp.79-92
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• 1994

The objectives of this study were to examine whether there were differences in family cohesion and adaptability perceived by married women when socio-demographic variables authority patterns and sex-role attitudes changed. Dividing the family system type into two parts by the levels of cohesion and adaptability then collected data were examined to test curviliner and linear hypothesis. The subjects were 542 married women living in Pusan. The guestionnaires included FACES III Authority Pattern and Sex-role attitude scales. The data were analyzed with statistical methods such as Frequency Distribution Percentile Mean T-test and X2-test. The major findings were as follows: 1) The levels of family cohesion and family adaptability perceived by married women were high. 2) There were no significant statistical differences in the levels of socio-demographic variables Authority pattern Sex-role attitude among the groups of family system type I based on the curvilinear hypothesis but significant statistical differences were found in preferred variables among the groups of family system type II based on the linear hypothesis. 3) Among the socio-demographic variables family type religion and husband's educational level were significantly correlated with the groups of family system type II,. The percentiles of HH(the levels of cohesion and adaptability were high) families were high when the married women's sex-role attitudes leaned toward modern and authority patterns were husband-dominant.

• Communications for Statistical Applications and Methods
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• v.17 no.2
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• pp.241-253
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• 2010

As standard unit root tests are empirically proved to fail to reject the null hypothesis of a unit root for many economic and business time series, it is doubtful that most of those series are informative about the existence of a unit root or that those tests are powerful against relevant alternative hypotheses. This study attempts to perform tests of the null hypothesis of stationarity as well as tests of the null hypothesis of a unit root using the time series data of housing prices in the major metropolitan areas. The results of the additional analyses such as lead-lag, cross-correlation and impulse response for testing the statistical interrelationships between the prices are generally found to be consistent.

• Structural Engineering and Mechanics
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• v.26 no.5
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• pp.499-516
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• 2007

An experimental method denoted as Impulse Method is proposed as a cost-effective non-destructive technique for the on-site evaluation of concrete elastic modulus in existing structures: on the basis of Hertz's quasi-static theory of elastic impact and with the aid of a simple portable testing equipment, it makes it possible to collect series of local measurements of the elastic modulus in an easy way and in a very short time. A Hypothesis Testing procedure is developed in order to provide a statistical tool for processing the data collected by means of the Impulse Method and assessing the possible occurrence of significant variations in the elastic modulus without exceeding some prescribed error probabilities. It is based on a particular formulation of the renowned sequential probability ratio test and reveals to be optimal with respect to the error probabilities and the required number of observations, thus further improving the time-effectiveness of the Impulse Method. The results of an experimental investigation on different types of plain concrete prove the validity of the Impulse Method in estimating the unknown value of the elastic modulus and attest the effectiveness of the proposed Hypothesis Testing procedure in identifying significant variations in the elastic modulus.

• Communications for Statistical Applications and Methods
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• v.25 no.1
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• pp.1-13
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• 2018

In many studies, a researcher attempts to describe a population where units are measured for multiple outcomes, or responses. In this paper, we present an efficient procedure based on ranked set sampling to estimate and perform hypothesis testing on a multivariate mean. The method is based on ranking on an auxiliary covariate, which is assumed to be correlated with the multivariate response, in order to improve the efficiency of the estimation. We showed that the proposed estimators developed under this sampling scheme are unbiased, have smaller variance in the multivariate sense, and are asymptotically Gaussian. We also demonstrated that the efficiency of multivariate regression estimator can be improved by using Ranked set sampling. A bootstrap routine is developed in the statistical software R to perform inference when the sample size is small. We use a simulation study to investigate the performance of the method under known conditions and apply the method to the biomarker data collected in China Health and Nutrition Survey (CHNS 2009) data.

• Journal of Global Scholars of Marketing Science
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• v.10
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• pp.91-110
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• 2002

The purpose of this research is as follows; First, the reference price ads are to investigate how the price cues and prior knowledge of service products have an effect on consumers' perception by the type of information. Second, this study suggests some marketing strategy guides to service marketing managers for price promotion strategy. To achieve these research goals, the hypothesis was established through reviewing the previous studies and the data collected from the experimental design. The experiment of this study was a 2$\times$2$\times$2 among the subject factorial design in which the factors were present in price cue presentation (presentation/non- presentation), the level of prior knowledge(high/low), and the type of information(positive/negative). The major findings of this research can be summarized as follows; First, there are some significant statistical differences in the consumers' perception value by level of price cues(hypothesis 1). Second, there are some significant statistical differences in the consumers' price-quality perception by level of price cues(hypothesis 2). Third, there are some significant statistical differences in the price-quality perception by the level of prior knowledge and the type of information(hypothesis 3).