• Information Systems Review
• /
• v.3 no.2
• /
• pp.289-303
• /
• 2001

The online stock transactions are gaining popularity at an incredible speed these days as more and more investors are adopting Internet as a new and convenient way of handling such transactions. As a consequence, the market for online stock exchange services is getting increasingly competitive; measuring and managing the quality of such services have become a crucial issue to the survival and growth of the stock brokerage houses. Unfortunately, however, little research effort to date has been made as to developing a set of valid and reliable measures for assessing investor perceptions of the quality of the online stock exchange service. The present study generates and tests a new set of multi-item measures for the quality of the online stock exchange service from an investor's perspective. This set of measures can be used in various stages and aspects of formulating online marketing strategies for stock brokerage firms. Marketing implications of this instrument for service providers are discussed.

• Korean Journal of Psychosomatic Medicine
• /
• v.20 no.2
• /
• pp.127-134
• /
• 2012

Objectives : Perceived stress scale is a self-report inventory to estimate the degree of individual perceived stress in daily life. The aim of this study was to introduce this scale and test the reliability and validity of the Korean version of PSS. Methods : The total of 154 female hospital workers were included in this study. The survey questionnaires were conducted for demographic information. All participants were required to complete PSS, Hamilton Anxiety scale and Beck Depression Inventory. Reliability and validity studies were conducted and internal consistency was examined. Results : The mean score of the PSS reported in this sample was $20.69{\pm}4.56$. The overall Cronbach's alpha was 0.819, and the test-retest reliability coefficient was 0.66. PSS had a significant positive correlation with the HAM-A(r=0.49, p<0.01), and the BDI(r=0.55, p<0.01). Factor analysis yielded 2 factors with eigenvalues of 3.924 and 2.608, accounting for 65 percent of variance. Factor 1 represented "stress" and factor 2 represented "control of stress". Conclusions : This study indicates that the PSS is appropriate for estimating the perceived stress levels. These results support the use of PSS in large sections of the population in Korea.

• Proceedings of the Korea Society for Simulation Conference
• /
• 1997.04a
• /
• pp.66-71
• /
• 1997

생존 트래픽 비율로만 정의되는 기존의 생존도는 통신 재난시 트래픽의 상대적 중 요도와 복구기간에 대한 생존도를 적절히 반영하지 못한다. 따라서 트래픽의 상대적 중요도 에 따라 트래픽을 복구함으로써 재난의 사회적 영향을 최소화하고 복구기간을 반영하는 새 로운 평가척도로서 재난영향 평가척도를 제시한다. DCS 전송망에 대해 제시한 재난 영향 평가척도 및 기존의 생존도를 계산하기 위하여 통신재난 시나리오 분석 시스템을 이용한다. 통신재난 시나리오 분석 시스템[1]은 장애발생, 복구방법 및 복구과정 관련 시나리오등으로 구성되므로 DCS 전송망에 대한 생존도 계산이 가능하다. 통신재난 시나리오 분석 시스템을 이용하여 다양한 전송망에 대해 얻은 재난영향 평가척도 결과 및 기존 생존도 결과를 비교 하였다.

• The Journal of Korean Association of Computer Education
• /
• v.21 no.5
• /
• pp.61-68
• /
• 2018

Collaborative filtering is a fundamental technique implemented in many commercial recommender systems and provides a successful service to online users. This technique recommends items by referring to other users who have similar rating records to the current user. Hence, similarity measures critically affect the system performance. This study addresses problems of previous similarity measures and suggests a new similarity measure. The proposed measure reflects the subjectivity or vagueness of user ratings and the users' rating behavior by using fuzzy logic. We conduct experimental studies for performance evaluation, whose results show that the proposed measure demonstrates outstanding performance improvements in terms of prediction accuracy and recommendation accuracy.

• Korean Journal of Social Welfare
• /
• v.59 no.4
• /
• pp.273-296
• /
• 2007

In this Study, to reconstruct the disability identity scale(Lee and Shin, 2006)), Rasch rating scale model was applied to the four sub-dimensions of the Disability Identity Scale in a sample of spinal cord injuries(N=397). The Disability Identity Scale was verified by explorative factor analysis and confirmatory factor analysis. However, factor analytic procedures can't evaluate item-fit indices, item difficulty, and appropriate scale category. A number of limitations posed by confirmatory factor analytic procedures can be averted with the use of Rasch rating scale model which is in the item response theory(IRT). So in this study, Rasch model was applied to the Disability Identity Scale. Results revealed that (A) 20 items were selected from Rasch model, (B) the difficulty level of the Disability Identity Scale was the average level, (C) 4-point rating scale was appropriate for the Disability Identity Scale. Finally, we could suggest that the sub-dimensions concepts of the disability identity became clearer and items were to the good fitting.

• 한국경영정보학회:학술대회논문집
• /
• 2007.11a
• /
• pp.597-602
• /
• 2007

본 연구는 추천시스템에서 협업필터링 알고리즘을 이용하여 특정 상품에 대한 고객의 선호도를 예측함에 있어 고객이 상품에 대해 평가한 선호도 평가치를 고객별로 표준화시켜 예측하여 기존의 예측 정확도를 향상시키는 방법에 대하여 연구하였다. 일반적으로 상품에 대한 고객의 선호도를 평가하기 위하여 절대적 기준의 수치적 척도가 제공되지만 개인에 따라서는 상품에 대한 선호 정도가 절대적 척도에 다르게 반영되어 개인별 선호도에 차이가 발생할 수 있다. 이러한 개인적 특성이 동일한 척도의 평가치로 예측되면 예측 결과의 오차를 크게 할 가능성이 있다. 또한 개인이 평가한 선호도 평가치의 편차가 협업필터링 알고리즘을 통한 선호도 예측 정확도와 밀접한 관계를 가지고 있음을 알 수 있었으며 이러한 문제를 해결하기 위하여 개별 고객이 평가한 선호도 평가치를 표준화시켜 표준화된 선호도 평가치를 이용한 선호도 예측을 실시하였다. 분석결과 표준화된 선호도 평가치를 이용한 예측 결과가 비표준화 선호도 평가치를 이용한 예측 결과보다 예측력이 우수함을 알 수 있었으며 결과에 대한 통계적 분석을 통하여 표준화된 선호도 평가치를 이용한 선호도 예측 방법과 비 표준화 선호도 평가치를 이용한 선호도 예측 방법을 혼합할 경우 선호도 예측 정확도를 더 향상시킬 수 있음을 알 수 있었다.

• 한국경영정보학회:학술대회논문집
• /
• 2007.11a
• /
• pp.111-116
• /
• 2007

체계적인 정보화 투자 및 관리를 위한 전사적 아키텍처(EA)를 도입한 기관과 기업이 늘어남에 따라, EA 도입의 성과를 명확하게 평가해야 할 필요성도 높아지고 있다. EA를 도입한 나라의 약 36%에서 EA의 도입 현황과 성과를 측정하고 있으며, 국내에서도 범정부 정보기술아키텍처 성숙도 평가모형을 개발하는 등, 다양한 접근 방법으로 EA 평가를 위한 방안을 연구하고 있다. 그러나 EA를 통해 추구하는 목적이 매우 다양하고, EA의 활용과 관리에 대한 표준체계가 없어 EA 평가모형의 적용 범위와 효용성은 매우 제한적이다. 본 연구는 조직의 EA 평가목적에 적합한 평가 대상 및 척도를 체계적으로 도출하기 위한 EA 평가모형 개발 프레임워크를 제안한다. 프레임워크는 IEEE Std 1471의 아키텍처 표현 개념 프레임워크를 EA에 적용하여 EA 평가모형 체계를 구성하고, EA 내부와 외부 이해당사자의 관심사항을 토대로 GQM 기법을 적용하여 EA 평가의 대상인 관점(viewpoint)과 평가 척도(metric)를 도출한다. 제안된 프레임워크를 적용하면 기업 및 조직의 EA 이해당사자가 의도하는 목적이 반영된 EA 평가모형을 개발할 수 있다. 모형의 상세화와 더불어 프레임워크를 실무에 적용하기 위해서 필요한 객관적인 평가기준과 모형 개발과 적용을 지원하는 도구에 대한 연구가 향후 과제이다.

• Proceedings of the Korean Operations and Management Science Society Conference
• /
• 1989.10a
• /
• pp.30-39
• /
• 1989

일반적으로 cluster의 수가 미정인 상황하에서의 clustering문제는 semistructured문제로 알려져 있다. clustering문제를 구조화하는데 있어서 해의 품질평가(evaluation of solution quality)가 필수적이나 각 응용분야에 널리 적용될 수 있는 척도는 아직까지 개발되어있지 못한 상태이다. 그 주된 원인은 cluster해에 대한 개념적 차원에서의 평가기준은 제시되어있으나 척도의 구현에 있어서는 제시된 개념들이 명확하게 적용될 정도의 수준으로는 구체화되지 못한데에 기인한다고 할 수 있다. 본 연구의 목적은 개체차원이 다차원으로 확장된 clustering문제를 대상으로하는 clustering문제의 척도개발에 있다.

• Journal of the Korea Computer Industry Society
• /
• v.4 no.4
• /
• pp.467-478
• /
• 2003

The purpose of this paper is to develop and to introduce the rubrics for performance assessment, which can measure elementary school upper graders' ability to use ICT, With a goal of improving their ability to use ICT, the students, who are in the fourth, fifth, six grades, received instructions on the basic skills and knowledge for using the computer during the extracurricular-activity session or the self-directed session after regular classes. In the study, the rubrics were developed on the basis of the 7th national curriculum, and defined respectively assessment criteria and attainment targets for the upper graders. The assessment criteria were set after the researcher determined the most basic and important skills and knowledge that the upper graders should have, and then compared them with the attainment criteria in the national curriculum. Accordingly, the application of the rubrics developed for this study is expected to lessen the burden of elementary school teachers when they implement performance assessment in their classrooms. Finally, using the rubrics, the study assessed elementary school students' ability to use the computer, and showed somewhat limiting but satisfactory results.

• Journal of Korea Multimedia Society
• /
• v.5 no.4
• /
• pp.405-414
• /
• 2002

In this paper, we propose a new objective speech quality measure using noise masking threshold for speech quality assessment of mobile telephone network environments, and verify the effectiveness of the proposed method through the experiments. For such a purpose, well known objective speech quality measures such as BSD and PSQM are first evaluated for digital mobile telephone network environments. However, these conventional methods does not have good performance under mobile networks environments compared to literary results. To be mote effective objective speech quality measure under mobile telephone environments, the proposed method employs human psychoacoustic masking effect. The DMOS, instead of MOS, is used as a subjective speech quality measure for performance evaluation. The performance comparison are carried out with speech data collected from digital mobile telephone environments. As results, the proposed measure have and average 4% higher performance, in terms of correlation, than existing objective speech quality measures such as BSD and PSQM.