• Journal of the Korean Statistical Society
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• 제27권4호
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• pp.471-483
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• 1998

The influence of observations on the misclassification probability in multiple discriminant analysis under the equal covariance assumption is investigated by the local influence method. Under an appropriate perturbation we can get information about influential observations and outliers by studying the curvatures and the associated direction vectors of the perturbation-formed surface of the misclassification probability. We show that the influence function method gives essentially the same information as the direction vector of the maximum slope. An illustrative example is given for the effectiveness of the local influence method.

• Communications for Statistical Applications and Methods
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• 제12권2호
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• pp.453-462
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• 2005

We derive the influence function on t statistic and find its feature; the influence function on t statistic has two forms depending on the value of ${\mu}_0$. Sample influence functions are used to verify the validity of the derived influence function. We use random samples from normal distribution to show the validity of the function. The simulation study proves that the obtained influence function is very accurate to in estimating changes in t statistic when an observation is added or deleted.

• Journal of Information Science Theory and Practice
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• 제1권2호
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• pp.36-57
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• 2013

Blogs are readily available sources of opinions and sentiments which allows bloggers to exert a certain level of influence over the blog readers. Previous studies had attempted to analyze blog features to detect influence within the blogosphere, but had not studied in details influence at the blogger-level. Other studies studied bloggers' personalities with regards to their propensity to blog, but did not relate the personalities of bloggers to influence. Bloggers may differ in their way or manner of exerting influence. For example, bloggers could be active participants or just passive shares, or whether they express ideas in a rational or subjective manner, or they are received positively or negatively by the readers. In this paper, we further analyze the engagement style (frequency, scope, originality, and consistency of the blog postings), persuasion style (appeals to reasons or emotions), and persona (degree of compliance) of individual bloggers. Methods used include similarity analysis to detect the sharing-creating aspect of engagement style, subjectivity analysis to measure persuasion style, and sentiment analysis to identify persona style. While previous studies analyzed influence at blog site level, our model is shown to provide a fine-grained influence analysis that could further differentiate the bloggers' influence style in a blog site.

• 응용통계연구
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• 제33권5호
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• pp.527-540
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• 2020

이상치에 대한 적절한 선별과 배제없이 모든 데이터를 종합적으로 분석하게 되는 경우 데이터 분석을 통해 얻은 결과의 신뢰성과 해석의 일반성에 치명적인 위협을 받을 수 있다. 따라서 데이터의 분석 과정에서 이러한 이상치를 판별하고, 이상치가 통계량, 통계적 모형에 어떠한 영향을 주는 지에 대한 분석은 매우 중요한 일이라 할 수 있다. Hampel이 영향함수를 활용하여 이상치를 판별할 수 있는 방법을 소개한 이후, 이상치를 판별하기 위한 방법론으로 영향함수가 폭넓게 활용되어 왔다. 영향함수에는 경험적 영향함수와 표본영향함수가 있으며, 경험적 영향함수를 활용해 표본영향함수를 근사 추론하여 하나의 관측값이 제거되었을 때 통계량에 미치는 영향을 예측하는 방법론이 주로 활용되었다. 본 연구에서는 표본평균, 표본분산, 표본표준편차의 표본영향함수 유도를 통해 경험적 영향함수와 표본영향함수의 차이를 살펴 본다. 또한 경험적 영향함수로 표본영향함수를 근사하는 과정에서 발생하는 오차를 줄이기 위해 경험적 영향함수의 보정으로 표본영향함수를 근사 추론하는 방법을 제안하고, 모의실험을 통해 제안한 추론 방법의 타당성을 확인한다.

• Journal of applied mathematics & informatics
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• 제13권1_2호
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• pp.479-485
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• 2003

The influence of observations on the Wilks' lambda test of a linear hypothesis in multivariate regression is investigated using the local influence method. The perturbation scheme of case-weights is considered. A numerical example is given to show the effectiveness of the local influence method in identifying the influential observations.

• 가정과삶의질연구
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• 제27권3호
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• pp.15-30
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• 2009

This study explored the level and general propensity of consumption-oriented attitude and impulsive buying behavior of high school students, and clarified factors affecting impulsive buying. The research results can be summarized as follows. 1. The degree of consumption-oriented attitude and impulsive buying behavior of high school students were relatively low. 2. Consumption-oriented attitude was found to have significant differences among students based on monthly allowance, self-esteem, influence of friends, influence of mass media and influence of consumer education at school. Moreover, impulsive buying behavior was found to have significant differences according to sex, level of parents's education, fathers job, monthly household income, monthly allowance, influence of home, influence of friends and influence of mass media. 3. The impulsive buying differed significantly according to consumption-oriented attitude. That is, the group showing a higher degree of consumption-oriented attitude also indicated higher impulsive buying. 4. The variables affecting the level of impulsive buying behavior were the level of consumption-oriented attitude, influence of mass media, influence of friends and sex. In other words, consumption-oriented attitude, influence of mass media and influence of friends had a positive affect, and female students were more apt to impulsive buying than male students.

• 유통과학연구
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• 제15권2호
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• pp.37-46
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• 2017

Purpose - This research investigates whether e-service quality has the influence on long-term orientation, consumer commitment, and satisfaction. Research design, data, and methodology - Data collection took place for 30 days from October 1, 2015 to October 31, 2015. 315 copies had been analyzed. Covariance structure analysis with credibility and factor analysis was conducted to verify this research hypotheses. Results - First, the lower dimension concepts of e-service quality, reliability, and tangibility had a significant influence on customer commitment, and responsiveness had a significant negative influence. However, aesthetics did not have a significant influence on that. Secondly, aesthetics had a significant influence on long-term orientation, but reliability, tangibility, and responsiveness did not have a significant influence. Thirdly, reliability, tangibility, and aesthetics had a positive influence on customer satisfaction. However, responsiveness had a negative influence. Fourthly, customer commitment had a significant and positive influence on customer satisfaction, but customer commitment and customer satisfaction had a negative influence on long-term orientation. Conclusions - This research verifies the influencing relationship between e-service quality of a franchise coffee shop application with customer commitment, customer satisfaction, and long term orientation. By the results of this research, possibility of application and expansion of theory has been proven.

• 대한가정학회지
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• 제44권12호
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• pp.93-103
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• 2006

The purpose of this study was to understand the consumption of adolescents by investigating the influences on their clothing purchasing influence and the effects of family communication and clothing interest. The questionnaires used for the were conducted for this study analysis was and were distributed to four Middle schools and two High schools which were located in Seoul. and 576 responses questionnaire were used for data analysis. Using SPSS package, factor analysis, reliability, Pearson correlation, regression, ANOVA, Duncan's Multiple Range test, and t-test were applied. The study results of this study are as follows: First, the influence of clothing purchasing influence of adolescents was higher than the parents' purchasing influence. Second, there were negative correlations between two levels of family communication, controlled and opened communication. But, but positive correlations between controlled communication and clothing interest, and between clothing interest and purchasing influence there were positive correlations. Third, there were partially significant differences among demographic factors and levels of communications, clothing interest and purchasing influence. Fourth, for male students social status, opened communication, and clothing interest had an effect on purchasing influence for male students and for female students clothing interest and both controlled and opened communication influenced were affecting purchasing influence for female students.

• 한국지역사회생활과학회지
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• 제28권2호
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• pp.313-328
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• 2017

The purpose of this study was to analyze the role of perceived market influence, which is an important psychological factor influencing consumer behavior in the market, and explain how consumer beliefs related to the market can affect sustainable consumer behavior. First, this study found that gaps in perceived market influence were statistically significant for age and job. Second, environmental concern, organic food consumption (vegetables and meats), and purchase behavior of organic foods were found to be significantly different by degree of perceived market influence of consumers. The mean values were found to be high for the group having strong perceived market influence. This tendency suggests an association between higher perceived market influence consumers and more environmentally friendly consumer behavior. Lastly, this study used Structural Equation Modeling to analyze the effect of perceived market influence as a moderating variable and mediating variable on the relationship between environmental concerns and consumer behavior toward organic foods. The results show a mediating effect on perceived market influence, but a moderating effect could not be found. This result implies that perceived market influence might indirectly affect consumer behavior when transferring environmental concerns to consumer behavior toward organic foods.

• 유통과학연구
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• 제14권10호
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• pp.21-27
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• 2016

Purpose - This study analyzes economic relations and mutual influence in the global equipment manufacturing industry (EMI) and China's influence. Research design, data, and methodology - Data were collected from the World Input-Output Database (WIOT), looking at 16 countries. The sample time period was 2002-2011. Influence and motivation coefficients were calculated. Results - 1) China's EMI showed a very strong influence coefficient, even surpassing world industrial powers like Japan, the USA, Germany, and Korea. 2) As for influence on added-value, China's EMI motivation coefficient was ranked third in 2011, which meant it had a negligible effect on added-value. 3) From 2002 to 2011, both the influence and motivation coefficients of China's EMI rose. Conclusions - China's EMI has strong influence and motivation coefficients. It has a significant impact on the world EMI, especially on the total output of the global EMI. Additionally, during 2002 to 2011, the ranking of China's EMI motivation coefficient improved year over year, and its economic efficiency obviously improved. By 2011, China's EMI's international influence was second only to the US and Japan.