• 제목/요약/키워드: Review variance

검색결과 312건 처리시간 0.022초

남성 직장인의 절주행위 측정도구 개발 -Ajzen의 계획적 행위 이론 적용- (Constructing a Questionnaire on Male Workers' Sobriety Behavior - Based on Ajzen's Theory of Planned Behavior -)

  • 박인혜;김윤경
    • 지역사회간호학회지
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    • 제21권2호
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    • pp.156-168
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    • 2010
  • Purpose: The purpose of this study was to construct a questionnaire to assess male workers' sobriety behavior based on Ajzen's Theory of Planned Behavior (TPB). Methods: A primary questionnaire with 56 questions was constructed based on literature review and structured interview with male workers. The Content Validity Index (CVI) was evaluated by a group of experts, construct validity was tested by principle component analysis, and reliability was evaluated by Cronbach's ${\alpha}$ and the test-retest reliability test. Results: Fifty two questions showed higher than .8 of CVI. Four factors explained 78.71% of the total variance among items for sobriety intention and direct measure, and six factors explained 67.99% of the total variance among indirect measure items and those factors coincided with the variables of TPB in factor analysis. Cronbach's ${\alpha}$ of this questionnaire was .873 and the result of test-retest reliabilty test was relatively reliable. A total of 41 items with 7-point scale were constructed in the final version. Conclusion: This questionnaire was valid and reliable to measure sobriety behavior based on TPB in male workers. It can be useful to evaluate the result of a sobriety program for male workers.

환율 변동성 측정과 GARCH모형의 적용 : 실용정보처리접근법 (Exchange Rate Volatility Measures and GARCH Model Applications : Practical Information Processing Approach)

  • 문창권
    • 통상정보연구
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    • 제12권1호
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    • pp.99-121
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    • 2010
  • This paper reviews the categories and properties of risk measures, analyzes the classes and structural equations of volatility forecasting models, and presents the practical methodologies and their expansion methods of estimating and forecasting the volatilities of exchange rates using Excel spreadsheet modeling. We apply the GARCH(1,1) model to the Korean won(KRW) denominated daily and monthly exchange rates of USD, JPY, EUR, GBP, CAD and CNY during the periods from January 4, 1998 to December 31, 2009, make the estimates of long-run variances in the returns of exchange rate calculated as the step-by-step change rate, and test the adequacy of estimated GARCH(1,1) model using the Box-Pierce-Ljung statistics Q and chi-square test-statistics. We demonstrate the adequacy of GARCH(1,1) model in estimating and forecasting the volatility of exchange rates in the monthly series except the semi-variance GARCH(1,1) applied to KRW/JPY100 rate. But we reject the adequacy of GARCH(1,1) model in estimating and forecasting the volatility of exchange rates in the daily series because of the very high Box-Pierce-Ljung statistics in the respective time lags resulting to the self-autocorrelation. In conclusion, the GARCH(1,1) model provides for the easy and helpful tools to forecast the exchange rate volatilities and may become the powerful methodology to overcome the application difficulties with the spreadsheet modeling.

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확산모형에 대한 NLL 추정법의 특성과 적용 (Review and Applications of NLL Estimation Method for Diffusion Processes)

  • 홍진영;이윤동
    • Communications for Statistical Applications and Methods
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    • 제17권4호
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    • pp.599-609
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    • 2010
  • 확산모형은 금융현상을 모형화하기 위한 방법으로 자주 사용된다. 다양한 확산모형들을 추론하기 위한 다양한 추론기법들이 제안되어져 왔다. 본 연구에서는 시뮬레이션 방법을 통하여 Shoji와 Ozaki (1998)에 의하여 제안된 NLL 방법의 성질을 검토하여 보고, 실제 자료에 적용하게 된다.

국제물류에서 해운물류기업의 공급사슬성과 결정요인 (A Determinant Factors on Supply Chain Performance of Shipping and Logistics Firm in International Logistics)

  • 윤광운;배희성
    • 무역상무연구
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    • 제30권
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    • pp.3-26
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    • 2006
  • Supply chain is viewed as a number of organizations(at least three) working cooperatively with at least some shared objectives. The concept of supply chain management represents the most advanced state in the evolutionary development of purchasing, procurement and other supply chain activities. This study aims to analyze and develop a measurement instrument for supply chain performance in international logistics. A measurement instrument for supply chain performance in international logistics are developed by Lai et al(2002). Supply chain reliability, customer service and cost are constructed reflecting service effectiveness and operations efficiency between shipper, forwarder and liner. The results of this study are as follow. We firstly tested the measurement properties of the sub-dimension of the supply chain performance construct using reliability test and confirmatory factor analysis follow by exploratory factor analysis. For each of the factor, reliability and validity are achieved because of the significant loading of the measurement items on their latent factors. Further research perform the analysis of variance by multi respondents within each firm and across partner firms in the supply chain. The result of analysis present the difference with shipper, forwarder and liner in statistics.

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인공신경망을 이용한 로버스트설계에 관한 연구 (Robust Parameter Design Based on Back Propagation Neural Network)

  • ;김영진
    • 경영과학
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    • 제29권3호
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    • pp.81-89
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    • 2012
  • Since introduced by Vining and Myers in 1990, the concept of dual response approach based on response surface methodology has widely been investigated and adopted for the purpose of robust design. Separately estimating mean and variance responses, dual response approach may take advantages of optimization modeling for finding optimum settings of input factors. Explicitly assuming functional relationship between responses and input factors, however, it may not work well enough especially when the behavior of responses are poorly represented. A sufficient number of experimentations are required to improve the precision of estimations. This study proposes an alternative to dual response approach in which additional experiments are not required. An artificial neural network has been applied to model relationships between responses and input factors. Mean and variance responses correspond to output nodes while input factors are used for input nodes. Training, validating, and testing a neural network with empirical process data, an artificial data based on the neural network may be generated and used to estimate response functions without performing real experimentations. A drug formulation example from pharmaceutical industry has been investigated to demonstrate the procedures and applicability of the proposed approach.

백화점의 정보품질과 서비스품질이 서비스만족도에 미치는 영향 -경남지역 백화점을 중심으로- (Impact of Information Support Quality and Service Quality Factors on Service Satisfaction of Department Store -Case Study of Kyungnam Area Department Store-)

  • 김동일;최승일
    • 한국콘텐츠학회논문지
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    • 제7권7호
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    • pp.133-143
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    • 2007
  • 본 연구의 목적은 정보품질과 서비스품질이 백화점의 서비스 만족도에 미치는 영향과 효과를 실증적으로 분석하는데 있다. 이러한 연구목적을 달성하기 위하여 문헌연구와 요인분석, 분산분석, 회귀분석을 이용한 실증적 연구를 함께 실시하였다. 본 연구의 분석결과는 다음과 같다. 첫째, 회귀분석결과 정보품질과 서비스 만족도와의 관계는 통계적 유의성이 매우 높게 분석되었다. 둘째, 분산분석에서 서비스품질에 따라 정보만족과 서비스기대치와의 관계도 유의성이 있는 것으로 나타났다. 결과적으로 정보지원체계와 서비스품질은 고객과의 관계에 있어서 주요한 요인으로 분석되었다.

시계열 계속 표본조사에서 불균등확률 추출법 연구 (A study on unequal probability sampling over two successive occasions in time series)

  • 박홍래;이계오
    • 응용통계연구
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    • 제6권1호
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    • pp.145-162
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    • 1993
  • 본 논문에서는 반복적 계속 표본조사에서 일부의 표본을 교체하는 2회 계속조사의 표본 추 출법들을 요약하고 앞 조사시기의 관찰값을 확률측도로 이용한 RHC(Rao-Hartley-Cochran) 유형의 불균등 확률추출법을 제안하였다. 제안된 추출법과 기존의 확률추출법의 비교를 위 하여 둘째 조사시기의 모평균 추정량과 그의 분산을 유도하였으며, 제안된 추출법의 상대 효율은 이론적인 측면과 수치적 시뮬레이션 방법으로 비교 분석되었다. 시뮬레이션 비교를 위하여 한 특별한 시계열 모형을 가정하고 이를 사용하여 인위적인 모집단을 생성하였으며 이 모집단에서 각 추출법에 해당되는 표본을 컴퓨터로 추출하여 각각의 추정치를 계산하여 비교한 결과에서 RHC 유형의 새로 제안된 추출법의 분산과 편차가 일반적으로 적음을 보 였다.

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표본조사에서 일반회귀 추정량의 활용 (General Regression Estimators in Survey Sampling)

  • 김규성
    • 한국조사연구학회지:조사연구
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    • 제5권2호
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    • pp.49-70
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    • 2004
  • 표본조사에서 사용 가능한 보조변수가 있는 경우에 추정의 효율을 높이기 위하여 보조변수를 활용하는 방법이 다각적으로 개발되어 왔다. 이 논문은 보조변수를 효과적으로 이용하는 방법 중의 하나인 일반회귀추정량에 대한 개괄적인 고찰이다. 일반회귀추정량의 출현부터 분산추정법의 제안까지 이론전개 과정을 살펴보았으며, 보정추정량 및 QR추정량과의 관련성을 통하여 일반회귀추정량의 성질을 알아보았다. 특히 분산추정에서 통상적인 설계기반 분산추정량이 가지는 조건부 성질의 약점을 보완하기 위하여 가중잔차기법을 사용하는 과정을 살펴보았다. 층화표집이나 집략표집과 같은 복합설계에서 활용할 수 있는 일반회귀추정량의 형태를 소개하였고, 마지막으로 일반회귀추정량의 장단점, 그리고 향후 이론적인 발전방향 및 실용적인 발전방향을 언급하였다.

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간호대학생의 학업탄력성과 대인관계유능성이 행복감에 미치는 영향 (Effects of Academic Resilience and Interpersonal Competence on the Happiness of Nursing Students)

  • 신수진;황은희
    • 의학교육논단
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    • 제20권3호
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    • pp.156-163
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    • 2018
  • The purpose of this study was to investigate the effects of academic resilience and interpersonal competence on the happiness of nursing students. A descriptive design was used to study 158 nursing students in nursing school through convenience sampling. IBM SPSS ver. 23.0 (IBM Corp., Armonk, NY, USA) was used to analyze data for descriptive statistics, t-test, analysis of variance, Tukey post hoc test, Pearson's correlations, and multiple regressions. The results showed that the level of nursing students' happiness was lower than that of college students in other majors, but academic resilience and interpersonal competence among nursing students were relatively high. Nursing students' happiness was positively correlated with academic resilience and interpersonal competence. The factors affecting happiness were academic resilience (${\beta}=0.459$, p<0.001), satisfaction with major (${\beta}=0.272$, p=0.006), perceived subjective health status (${\beta}=0.223$, p=0.013), and interpersonal competence (${\beta}=0.185$, p=0.003). Explained variance for happiness was 56.4%, and academic resilience was the most influential factor in the happiness of nursing students. Nursing students are caring human beings and should be able to pursue a happy life; therefore, it is necessary to improve satisfaction levels with the nursing major, guide students to excel in their academic achievement, prepare health education programs, and design curriculum that inspires confidence in interpersonal relationships.

A Review of Large-Scale Hydropower Project in Public Sector of Pakistan

  • Umair, Muhammad;Choudhary, Muhammad Abbas;Jahanzaib, Mirza
    • Journal of Construction Engineering and Project Management
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    • 제4권4호
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    • pp.47-59
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    • 2014
  • Client organization inadequate project planning before awarding the contract and insufficient monitoring and control system among the parties involved create severe problems. Ultimately, large-scale projects go beyond the expected cost and time control limits. This paper discusses the major issues involved with a large-scale Hydropower Project in Pakistan Public Sector environment. The latest approved Baseline Plan of project was reviewed and analyzed using Variance Analysis and Trend Analysis techniques in Primavera project management software to assess the efforts made of the parties involved. It was found that Project is 202% Cost overrun and 25% time delays from original contract award. After analysis of baseline plan and quantification of various variance issues in impacted activities, the questionnaire survey was conducted to identify the impact of causative factors. There were almost 17 most significant causative factors identified among 60 identified factors and responsibilities are assigned accordingly. At the end recommendations are made for strategic decisions as lessons learned during project evaluation.